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  • luffy_07

    07购物车实现

    创建子应用 cart

    cd luffy/apps
    python ../../manage.py startapp cart
    

    注册子应用cart

    INSTALLED_APPS = [
        'ckeditor',  # 富文本编辑器
        'ckeditor_uploader',  # 富文本编辑器上传图片模块
    
        'home',
        'users',
        'courses',
        'cart',
    ]
    

    因为购物车中的商品(课程)信息会经常被用户操作,所以为了减轻服务器的压力,可以选择把购物车信息通过redis来存储.

    配置信息

    # 设置redis缓存
    CACHES = {
        # 默认缓存
        ....
        
        "cart":{
            "BACKEND": "django_redis.cache.RedisCache",
            "LOCATION": "redis://127.0.0.1:6379/3",
            "OPTIONS": {
                "CLIENT_CLASS": "django_redis.client.DefaultClient",
            }
        },
    }
    

    接下来商品信息存储以下内容:

    course_id      购物车中的商品ID
    course_expire  购物车中商品的有效期
    is_selected    购物车中对应商品的勾选状态
    
    # 上面三个数据,实际上存储到redis中,要以什么类型来存储呢?
    # redis一共5种数据类型,我们就应该考虑到哪种数据类型保存上面的数据最方便我们读写.
    cart_<user_id>: {
      "商品ID1":"有效期",
      "商品ID1":"有效期",
      "商品ID1":"有效期",
    }
        
    # 把已经勾选的商品ID记录到无序集合中
    cart_selected_<user_id>:{
    	"商品ID1",
    	"商品ID2",
    	"商品ID3",
    }
    

    添加课程商品到购物车的API接口实现

    cart/views.py视图,代码:

    from django.shortcuts import render
    
    # Create your views here.
    from rest_framework.views import APIView
    from courses.models import Course
    from rest_framework.response import Response
    from django_redis import get_redis_connection
    from rest_framework.permissions import IsAuthenticated
    from rest_framework import status
    class CartAPIView(APIView):
        permission_classes = [IsAuthenticated]
        """购物车视图"""
        def post(self,request):
            """购物车添加商品"""
            # 获取客户端发送过来的课程ID
            course_id = request.data.get("course_id")
            # 验证课程ID是否有效
            try:
                Course.objects.get(pk=course_id,is_delete=False,is_show=True)
            except Course.DoesNotExist:
                return Response({"message":"当前课程不存在!"},status=status.HTTP_400_BAD_REQUEST)
    
            # 组装基本数据[课程ID,有效期]保存到redis
            redis = get_redis_connection("cart")
            # user_id = 1
            user_id = request.user.id
            try:
                # 添加一个成员到指定名称的hash数据中[如果对应名称的hash数据不存在,则自动创建]
                # hset(名称,键,值)
                redis.hset("cart_%s" % user_id, course_id, -1) # -1表示购买的课程永久有效
    
                # 添加一个成员到制定名称的set数据中[如果对应名称的set数据不存在,则自动创建]
                # sadd(名称,成员)
                redis.sadd("cart_selected_%s" % user_id, course_id )
    
            except:
                return Response({"message": "添加课程到购物车失败!请联系客服人员~"},status=status.HTTP_507_INSUFFICIENT_STORAGE)
    
            # 返回结果
            return Response({"message":"成功添加课程到购物车!"},status=status.HTTP_200_OK)
    

    提供访问路由

    总路由,代码:

    urlpatterns = [
    	...
        path('cart/', include("cart.urls")),
    ]
    

    子应用路由cart/urls.py,代码:

    from django.urls import path, re_path
    from . import views
    urlpatterns = [
        path(r"course/",views.CartAPIView.as_view()),
    ]
    

    默认用户添加课程到购物车就已经勾选了商品,视图代码:

    from django.shortcuts import render
    
    # Create your views here.
    from rest_framework.views import APIView
    from courses.models import Course
    from rest_framework.response import Response
    from django_redis import get_redis_connection
    from rest_framework.permissions import IsAuthenticated
    from rest_framework import status
    
    
    class CartAPIView(APIView):
        permission_classes = [IsAuthenticated]
        """购物车视图"""
        def post(self,request):
            """购物车添加商品"""
            # 获取客户端发送过来的课程ID
            course_id = request.data.get("course_id")
            # 验证课程ID是否有效
            try:
                Course.objects.get(pk=course_id,is_delete=False,is_show=True)
            except Course.DoesNotExist:
                return Response({"message":"当前课程不存在!"},status=status.HTTP_400_BAD_REQUEST)
    
            # 组装基本数据[课程ID,有效期]保存到redis
            redis = get_redis_connection("cart")
            # user_id = 1
            user_id = request.user.id
            # transation: 事务
            # 作用: 可以设置多个数据库操作看成一个整体,这个整理里面每一条数据库操作都成功了,事务才算成功,
            #      如果出现其中任意一个数据库操作失败,则整体一起失败!
            # 事务可以提供 提交事务 和 回滚事务 的功能
            # 不仅mysql中存在事务,在redis中也有事务的概念,但是叫"管道 pipeline"
            try:
                # 创建事务[管道]对象
                pipeline = redis.pipeline()
                # 开启事务
                pipeline.multi()
                # 添加一个成员到指定名称的hash数据中[如果对应名称的hash数据不存在,则自动创建]
                # hset(名称,键,值)
                pipeline.hset("cart_%s" % user_id, course_id, -1) # -1表示购买的课程永久有效
    
                # 添加一个成员到制定名称的set数据中[如果对应名称的set数据不存在,则自动创建]
                # sadd(名称,成员)
                pipeline.sadd("cart_selected_%s" % user_id, course_id )
    
                # 提交事务[如果不提交,则事务会自动回滚]
                pipeline.execute()
    
            except:
                return Response({"message": "添加课程到购物车失败!请联系客服人员~"},status=status.HTTP_507_INSUFFICIENT_STORAGE)
    
            # 返回结果
            return Response({"message": "成功添加课程到购物车!"}, status=status.HTTP_200_OK)
    

    前端提交课程到后端添加购物车数据

    Detail.vue

    <template>
        <div class="detail">
          <Header/>
          <div class="main">
            <div class="course-info">
              <div class="wrap-left">
                <video-player class="video-player vjs-custom-skin"
                   ref="videoPlayer"
                   :playsinline="true"
                   :options="playerOptions"
                   @play="onPlayerPlay($event)"
                   @pause="onPlayerPause($event)"
                >
                </video-player>
              </div>
              <div class="wrap-right">
                <h3 class="course-name">{{course.name}}</h3>
                <p class="data">{{course.students}}人在学&nbsp;&nbsp;&nbsp;&nbsp;课程总时长:{{course.lessons}}课时/{{course.lessons==course.pub_lessons?'更新完成':('已更新'+course.pub_lessons+"课程")}}&nbsp;&nbsp;&nbsp;&nbsp;难度:{{course.course_level}}</p>
                <div class="sale-time">
                  <p class="sale-type">限时免费</p>
                  <p class="expire">距离结束:仅剩 01天 04小时 33分 <span class="second">08</span> 秒</p>
                </div>
                <p class="course-price">
                  <span>活动价</span>
                  <span class="discount">¥0.00</span>
                  <span class="original">¥{{course.price}}</span>
                </p>
                <div class="buy">
                  <div class="buy-btn">
                    <button class="buy-now">立即购买</button>
                    <button class="free">免费试学</button>
                  </div>
                  <div class="add-cart" @click="cartAddHandle"><img src="/src/assets/cart-yellow.svg" alt="">加入购物车</div>
                </div>
              </div>
            </div>
            <div class="course-tab">
              <ul class="tab-list">
                <li :class="tabIndex==1?'active':''" @click="tabIndex=1">详情介绍</li>
                <li :class="tabIndex==2?'active':''" @click="tabIndex=2">课程章节 <span :class="tabIndex!=2?'free':''">(试学)</span></li>
                <li :class="tabIndex==3?'active':''" @click="tabIndex=3">用户评论 (42)</li>
                <li :class="tabIndex==4?'active':''" @click="tabIndex=4">常见问题</li>
              </ul>
            </div>
            <div class="course-content">
              <div class="course-tab-list">
                <div class="tab-item" v-if="tabIndex==1">
                  <div v-html="course.brief"></div>
                </div>
                <div class="tab-item" v-if="tabIndex==2">
                  <div class="tab-item-title">
                    <p class="chapter">课程章节</p>
                    <p class="chapter-length">共{{chapter_list.length}}章 147个课时</p>
                  </div>
                  <div class="chapter-item" v-for="chapter in chapter_list">
                    <p class="chapter-title"><img src="" alt="">第{{chapter.chapter}}章·{{chapter.name}}</p>
                    <ul class="lesson-list">
                      <li class="lesson-item" v-for="lesson in chapter.coursesections">
                        <p class="name"><span class="index">{{chapter.chapter}}-{{lesson.id}}</span> {{lesson.name}}<span class="free" v-if="lesson.free_trail">免费</span></p>
                        <p class="time">{{lesson.duration}} <img src=""></p>
                        <button class="try" v-if="lesson.free_trail"><router-link :to="{path: '/player',
                        query:{'vid':lesson.section_link}}">立即试学</router-link></button>
                        <button class="try" v-else>立即购买</button>
                      </li>
    
                    </ul>
                  </div>
                </div>
                <div class="tab-item" v-if="tabIndex==3">
                  用户评论
                </div>
                <div class="tab-item" v-if="tabIndex==4">
                  常见问题
                </div>
              </div>
              <div class="course-side">
                 <div class="teacher-info">
                   <h4 class="side-title"><span>授课老师</span></h4>
                   <div class="teacher-content">
                     <div class="cont1">
                       <img :src="course.teacher.image">
                       <div class="name">
                         <p class="teacher-name">{{course.teacher.name}} {{course.teacher.title}}</p>
                         <p class="teacher-title">{{course.teacher.signature}}</p>
                       </div>
                     </div>
                     <p class="narrative" >Linux运维技术专家,老男孩Linux金牌讲师,讲课风趣幽默、深入浅出、声音洪亮到爆炸</p>
                   </div>
                 </div>
              </div>
            </div>
          </div>
          <Footer/>
        </div>
    </template>
    
    <script>
    import Header from "./common/Header"
    import Footer from "./common/Footer"
    
    import {videoPlayer} from 'vue-video-player';
    
    export default {
        name: "Detail",
        data(){
          return {
            token:sessionStorage.token || localStorage.token,
            user_id:sessionStorage.id || localStorage.id,
            user_name:sessionStorage.username || localStorage.username,
            tabIndex:1,  // 当前选项卡显示的下标
            course_id:0, // 当前页面对应的课程ID
            course: {
                teacher: {},
            },  // 课程详情信息
            chapter_list:{},
            playerOptions: {
              playbackRates: [0.7, 1.0, 1.5, 2.0], // 播放速度
              autoplay: false, //如果true,则自动播放
              muted: false, // 默认情况下将会消除任何音频。
              loop: false, // 循环播放
              preload: 'auto',  // 建议浏览器在<video>加载元素后是否应该开始下载视频数据。auto浏览器选择最佳行为,立即开始加载视频(如果浏览器支持)
              language: 'zh-CN',
              aspectRatio: '16:9', // 将播放器置于流畅模式,并在计算播放器的动态大小时使用该值。值应该代表一个比例 - 用冒号分隔的两个数字(例如"16:9"或"4:3")
              fluid: true, // 当true时,Video.js player将拥有流体大小。换句话说,它将按比例缩放以适应其容器。
              sources: [{ // 播放资源和资源格式
                type: "video/mp4",
                src: "http://img.ksbbs.com/asset/Mon_1703/05cacb4e02f9d9e.mp4" //你的视频地址(必填)
              }],
              poster: "../static/courses/675076.jpeg", //视频封面图
               document.documentElement.clientWidth, // 默认视频全屏时的最大宽度
              notSupportedMessage: '此视频暂无法播放,请稍后再试', //允许覆盖Video.js无法播放媒体源时显示的默认信息。
            }
          }
        },
        watch:{
          course(data){
             // 替换视频地址
            this.playerOptions.sources[0].src = data.video;
            // 替换视频封面
            this.playerOptions.poster = data.course_img;
            // 替换科恒信息中的详情介绍里面的图片路径
            while(data.brief.search(`"/media`) != -1 ){
              data.brief = data.brief.replace(`"/media`,`"${this.$settings.Host}/media`)
            }
          },
          tabIndex(data){
            if(data==2){
              //获取当前课程对应的章节列表和课时列表
              this.$axios.get(`${this.$settings.Host}/courses/chapters/?course=${this.course_id}`).then(response=>{
                this.chapter_list = response.data;
              }).catch(error=>{
                console.log(error.response)
              })
            }
          }
        },
        created(){
          // 获取当前课程ID
          this.course_id = this.$route.query.id - 0;
          // 判断ID基本有效性
          let _this = this;
          if( isNaN(this.course_id) || this.course_id < 1 ){
            _this.$alert("无效的课程ID!","错误",{
              callback(){
                _this.$router.go(-1);
              }});
          }
          // 发送请求获取后端课程数据
          this.$axios.get(this.$settings.Host+`/courses/detail/${this.course_id}/`).then(response=>{
            this.course = response.data;
            // 修改视频中的封面图片
            this.playerOptions.poster = this.course.course_img;
          }).catch(error=>{
            console.log(error.response)
          });
    
    
        },
        methods: {
          // 视频播放事件
          onPlayerPlay(player) {
            alert("play");
          },
    
          // 视频暂停播放事件
          onPlayerPause(player){
            alert("pause");
          },
    
          // 视频插件初始化
          player() {
            return this.$refs.videoPlayer.player;
          },
    
          cartAddHandle(){
            // 判断客户是否登录
            if(!this.token){
              this.$confirm("对不起,您尚未登录!请登录", "提示").then(()=>{
                this.$router.push("/login");
              }).catch();}
    
            // 发起请求just
            console.log('just click it');
            this.$axios.post(this.$settings.Host + `/cart/course/`, {
              course_id: this.course_id,
            }, {
              headers: {
                //  注意:jwt后面必须有且只有一个空格!!!!
                "Authorization": "jwt "+this.token
              }
            }).then(response=>{
              // 获取购物车中商品总数
    
              // 添加购物车成功!
              this.$message(response.data.message, '提示', {
                duration: 2000,  // 单位:毫秒
              });
            }).catch(error=>{
              console.log(error.response);
            })
          }
    
        },
        components:{
          Header,
          Footer,
          videoPlayer,
        }
    }
    </script>
    
    

    后端增加返回一个购物车的商品课程总数

    from django.shortcuts import render
    
    # Create your views here.
    from rest_framework.views import APIView
    from courses.models import Course
    from rest_framework.response import Response
    from django_redis import get_redis_connection
    from rest_framework.permissions import IsAuthenticated
    from rest_framework import status
    class CartAPIView(APIView):
        permission_classes = [IsAuthenticated]
        """购物车视图"""
        def post(self,request):
            """购物车添加商品"""
            # 获取客户端发送过来的课程ID
            course_id = request.data.get("course_id")
            # 验证课程ID是否有效
            try:
                Course.objects.get(pk=course_id,is_delete=False,is_show=True)
            except Course.DoesNotExist:
                return Response({"message":"当前课程不存在!"},status=status.HTTP_400_BAD_REQUEST)
    
            # 组装基本数据[课程ID,有效期]保存到redis
            redis = get_redis_connection("cart")
            # user_id = 1
            user_id = request.user.id
            # transation: 事务
            # 作用: 可以设置多个数据库操作看成一个整体,这个整理里面每一条数据库操作都成功了,事务才算成功,
            #      如果出现其中任意一个数据库操作失败,则整体一起失败!
            # 事务可以提供 提交事务 和 回滚事务 的功能
            # 不仅mysql中存在事务,在redis中也有事务的概念,但是叫"管道 pipeline"
            try:
                # 创建事务[管道]对象
                pipeline = redis.pipeline()
                # 开启事务
                pipeline.multi()
                # 添加一个成员到指定名称的hash数据中[如果对应名称的hash数据不存在,则自动创建]
                # hset(名称,键,值)
                pipeline.hset("cart_%s" % user_id, course_id, -1) # -1表示购买的课程永久有效
    
                # 添加一个成员到制定名称的set数据中[如果对应名称的set数据不存在,则自动创建]
                # sadd(名称,成员)
                pipeline.sadd("cart_selected_%s" % user_id, course_id )
    
                # 提交事务[如果不提交,则事务会自动回滚]
                pipeline.execute()
    
            except:
                return Response({"message": "添加课程到购物车失败!请联系客服人员~"},status=status.HTTP_507_INSUFFICIENT_STORAGE)
    
            # 返回结果,返回购物车中的商品数量
            count = redis.hlen("cart_%s" % user_id)
    
            return Response({
                "message": "成功添加课程到购物车!",
                "count": count,
            }, status=status.HTTP_200_OK)
    
    

    前端展示商品课程的总数

    获取商品总数是在头部组件中使用到,并展示出来,但是我们后面可以在购物车中,或者商品课程的详情页中修改购物车中商品总数,因为对于一些数据,需要在多个组件中共享,这种情况,我们可以使用本地存储来完成,但是也可以通过vuex组件来完成这个功能。

    安装vuex
    npm install -S vuex
    
    
    把vuex注册到vue中
    1. 在src目录下创建store目录,并在store目录下创建一个index.js文件,index.js文件代码:

      import Vue from 'vue'
      import Vuex from 'vuex'
      
      Vue.use(Vuex);
      
      export const store = new Vuex.Store({
        // 数据仓库,类似vue里面的data
        state: {
      
        },
        // 数据操作方法,类似vue里面的methods
        mutations: {
      
        }
      });
      
      
    2. 把上面index.js中创建的store对象注册到main.js的vue中。

    // The Vue build version to load with the `import` command
    // (runtime-only or standalone) has been set in webpack.base.conf with an alias.
    import Vue from 'vue'
    import App from './App'
    
    import router from './routers/index';
    import store from './store/index';
    
    // 手动的自定义全局配置
    import settings from "./settings"
    Vue.prototype.$settings = settings;
    
    // elementUI 导入
    import ElementUI from 'element-ui';
    import 'element-ui/lib/theme-chalk/index.css';
    // 调用插件
    Vue.use(ElementUI);
    
    import "../static/css/reset.css"
    
    import axios from 'axios'; // 从node_modules目录中导入包
    
    // 允许ajax发送请求时附带cookie
    axios.defaults.withCredentials = true;
    
    Vue.prototype.$axios = axios; // 把对象挂载vue中
    
    
    Vue.config.productionTip = false;
    
    // 导入gt极验
    import '../static/js/gt.js';
    
    // vue-video视频播放插件
    require('video.js/dist/video-js.css');
    require('vue-video-player/src/custom-theme.css');
    import VideoPlayer from 'vue-video-player'
    Vue.use(VideoPlayer);
    
    /* eslint-disable no-new */
    new Vue({
      el: '#app',
      router,
      store,
      components: { App },
      template: '<App/>'
    })
    
    

    接下来,我们就可以在组件使用到store中state里面保存的共享数据了.

    先到vuex中添加数据,store/index.js,代码

    import Vue from 'vue'
    import Vuex from 'vuex'
    
    Vue.use(Vuex);
    
    export default new Vuex.Store({
      // 数据仓库,类似vue里面的data
      state: {
        // 购物车数据
        cart:{
          count:0,
        }
      },
      // 数据操作方法,类似vue里面的methods
      mutations: {
    
      }
    });
    
    
    

    在Header.vue头部组件中,直接读取store里面的数据

    <b class="goods-number">{{this.$store.state.cart.count}}</b>
    // this是可以省略不写。
    <b class="goods-number">{{$store.state.cart.count}}</b>
    
    

    我们可以在Detail.vue课程详情的组件中, 修改商品总数。

    // 添加商品课程到购物车
          cartAddHander(){
            // 1. 判断用户是否已经登录了.
            if(!this.token){
              this.$confirm("对不起,您尚未登录!请登录",'提示').then(() => {
                this.$router.push("/login");
              });
            }
    
            // 2. 发起请求
            this.$axios.post(this.$settings.Host+`/carts/course/`,{
              course_id: this.course_id,
            },{
              headers:{
                // 注意:jwt后面必须有且只有一个空格!!!!
                "Authorization":"jwt " + this.token
              }
            }).then(response=>{
    
              // 获取购物城中商品总数
              // this.$store.state.cart.count = response.data.count;
              this.$store.commit("addcart",response.data);
              // 添加购物车成功!
              this.$message(response.data.message,"提示!",{
                duration: 2000, // 单位: 毫秒
              });
    
            }).catch(error=>{
    
              console.log(error.response);
            })
          }
    
    

    在store/index.js中新增mutations的方法,代码:

    import Vue from 'vue'
    import Vuex from 'vuex'
    
    Vue.use(Vuex);
    
    export default new Vuex.Store({
      // 数据仓库,类似vue里面的data
      state: {
        // 购物车数据
        cart:{
          count: 0,
          // course_list: [], // 购物车里面的商品列表信息
        }
      },
      // 数据操作方法,类似vue里面的 methods
      mutations: {
        // data是调用方法,传递的购物车相关的参数
        addcart(state,data){
          // 修改商品课程的总数
          state.cart.count = data.count;
          // state.cart.course_list = data.course_list;
        }
      }
    });
    
    
    

    显示购物车商品列表数据

    后端提供获取购物车课程信息

        def get(self,request):
            """获取购物车中的所有课程信息"""
            # 获取当前登陆用户
            user_id = request.user.id
            # 从redis中获取所有的课程信息和勾选状态
            redis = get_redis_connection("cart")
            course_list = redis.hgetall("cart_%s" % user_id)
            selected_list = redis.smembers("cart_select_%s" % user_id )
            # 组装数据
            """
           cart_<user_id>:{
              课程id: 有效期,
              课程id: 有效期,
              课程id: 有效期,
           }
           cart_select_<user_id>:{课程id,课程id}
           
           上面两个数据最终要合并到一个数组中,一起返回给客户端
           [
            {
                course_id:课程id,
                course_expire:有效期,
                selected:True/False,  // 勾选状态
            },
           ]
           """
            data = []
            for course_id,price in course_list.items():
                course_id = course_id.decode()
                price = price.decode()
    
                try:
                    course_info = Course.objects.get(pk=course_id)
                except:
                    return Response({"message":"请求有误,请联系客服"},status=status.HTTP_507_INSUFFICIENT_STORAGE)
                data.append({
                    "id": course_id,
                    "price":price,
                    "selected": course_id.encode() in selected_list,
                    "course_img": course_info.course_img.url,
                    "name": course_info.name,
                })
    
            # 返回给客户端
            return Response(data,status=status.HTTP_200_OK)
    
    

    购物车页面有两部分构成:

    Cart.vue,代码:

    <template>
      <div class="cart">
        <Header/>
        <div class="cart-info">
            <h3 class="cart-top">我的购物车 <span>共1门课程</span></h3>
            <div class="cart-title">
               <el-row>
                 <el-col :span="2">&nbsp;</el-col>
                 <el-col :span="10">课程</el-col>
                 <el-col :span="4">有效期</el-col>
                 <el-col :span="4">单价</el-col>
                 <el-col :span="4">操作</el-col>
               </el-row>
            </div>
            <CartItem v-for="item in course_list" :course="item"/>
            <div class="calc">
                <el-row>
                  <el-col :span="2">&nbsp;</el-col>
                  <el-col :span="3">
                      <el-checkbox label="全选" name="type"></el-checkbox></el-col>
                  <el-col :span="2" class="del"><i class="el-icon-delete"></i>删除</el-col>
                  <el-col :span="12" class="count">总计:¥0.0</el-col>
                  <el-col :span="3" class="cart-calc">去结算</el-col>
                </el-row>
            </div>
        </div>
        <Footer/>
      </div>
    </template>
    
    <script>
      import Header from "./common/Header"
      import Footer from "./common/Footer"
      import CartItem from "./common/CartItem"
      export default {
        name:"Cart",
        data(){
          return {
            token: localStorage.token || sessionStorage.token,
            id: localStorage.id || sessionStorage.id,
            course_list:[]
          }
        },
        components:{
          Header,
          Footer,
          CartItem,
        },
        created(){
          // 判断用户是否已经登陆了。
          if( !this.token || !this.id ){
            this.$router.push("/login");
          }
          let _this = this;
          // 发起请求获取购物车中的商品信息
    
        }
      }
    </script>
    
    <style scoped>
    .cart{
      margin-top: 80px;
    }
    .cart-info{
      overflow: hidden;
       1200px;
      margin: auto;
    }
    .cart-top{
      font-size: 18px;
      color: #666;
      margin: 25px 0;
      font-weight: normal;
    }
    .cart-top span{
        font-size: 12px;
        color: #d0d0d0;
        display: inline-block;
    }
    .cart-title{
        background: #F7F7F7;
    }
    .cart-title .el-row,.cart-title .el-col{
        height: 80px;
        font-size: 14px;
        color: #333;
        line-height: 80px;
    }
    .calc .el-col{
      height: 80px;
      line-height: 80px;
    }
    .calc .el-row span{
      font-size: 18px!important;
    }
    .calc .el-row{
        font-size: 18px;
        color: #666;
        margin-bottom: 300px;
        margin-top: 50px;
        background: #F7F7F7;
    }
    .calc .del{
    
    }
    .calc .el-icon-delete{
      margin-right: 15px;
      font-size: 20px;
    }
    .calc .count{
      text-align: right;
      margin-right:62px;
    }
    .calc .cart-calc{
         159px;
        height: 80px;
        border: none;
        background: #ffc210;
        font-size: 18px;
        color: #fff;
        text-align: center;
        cursor: pointer;
    }
    </style>
    
    
    

    前端请求并显示课程信息

    Cart.vue

    <template>
      <div class="cart">
        <Header/>
        <div class="cart-info">
            <h3 class="cart-top">我的购物车 <span>共1门课程</span></h3>
            <div class="cart-title">
               <el-row>
                 <el-col :span="2">&nbsp;</el-col>
                 <el-col :span="10">课程</el-col>
                 <el-col :span="4">有效期</el-col>
                 <el-col :span="4">单价</el-col>
                 <el-col :span="4">操作</el-col>
               </el-row>
            </div>
            <CartItem v-for="item in course_list" :course="item"/>
            <div class="calc">
                <el-row>
                  <el-col :span="2">&nbsp;</el-col>
                  <el-col :span="3">
                      <el-checkbox label="全选" name="type"></el-checkbox></el-col>
                  <el-col :span="2" class="del"><i class="el-icon-delete"></i>删除</el-col>
                  <el-col :span="12" class="count">总计:¥0.0</el-col>
                  <el-col :span="3" class="cart-calc">去结算</el-col>
                </el-row>
            </div>
        </div>
        <Footer/>
      </div>
    </template>
    
    <script>
      import Header from "./common/Header"
      import Footer from "./common/Footer"
      import CartItem from "./common/CartItem"
      export default {
        name:"Cart",
        data(){
          return {
            token: localStorage.token || sessionStorage.token,
            user_id: localStorage.user_id || sessionStorage.user_id,
            course_list:[]  // 购物车中所有商品信息
          }
        },
        components:{
          Header,
          Footer,
          CartItem,
        },
        created(){
          // 判断用户是否已经登陆了。
          if( !this.token || !this.user_id ){
            alert("对不起,请登录")
            this.$router.push("/login");
          }
    
          // 发起请求获取购物车中的商品信息
          this.$axios.get(this.$settings.host+"/cart/course/").then(response=>{
            this.course_list = response.data;
          }).catch(error=>{
            console.log(error.response)
          })
        }
      }
    </script>
    
    <style scoped>
    .cart{
      margin-top: 80px;
    }
    .cart-info{
      overflow: hidden;
       1200px;
      margin: auto;
    }
    .cart-top{
      font-size: 18px;
      color: #666;
      margin: 25px 0;
      font-weight: normal;
    }
    .cart-top span{
        font-size: 12px;
        color: #d0d0d0;
        display: inline-block;
    }
    .cart-title{
        background: #F7F7F7;
    }
    .cart-title .el-row,.cart-title .el-col{
        height: 80px;
        font-size: 14px;
        color: #333;
        line-height: 80px;
    }
    .calc .el-col{
      height: 80px;
      line-height: 80px;
    }
    .calc .el-row span{
      font-size: 18px!important;
    }
    .calc .el-row{
        font-size: 18px;
        color: #666;
        margin-bottom: 300px;
        margin-top: 50px;
        background: #F7F7F7;
    }
    .calc .del{
    
    }
    .calc .el-icon-delete{
      margin-right: 15px;
      font-size: 20px;
    }
    .calc .count{
      text-align: right;
      margin-right:62px;
    }
    .calc .cart-calc{
         159px;
        height: 80px;
        border: none;
        background: #ffc210;
        font-size: 18px;
        color: #fff;
        text-align: center;
        cursor: pointer;
    }
    </style>
    
    
    

    CartItem.vue

    <template>
      <div class="cart-item">
              <el-row>
                 <el-col :span="2" class="checkbox"><el-checkbox v-model="course.selected" :checked="course.selected" name="type"></el-checkbox></el-col>
                 <el-col :span="10" class="course-info">
                   <img :src="this.$settings.host+course.course_img" alt="">
                    <span>{{course.name}}</span>
                 </el-col>
                 <el-col :span="4">
                     <el-select v-model="course.course_expire">
                        <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value"></el-option>
                      </el-select>
                 </el-col>
                 <el-col :span="4" class="course-price">¥{{course.price}}</el-col>
                 <el-col :span="4" class="course-delete">删除</el-col>
               </el-row>
      </div>
    </template>
    
    <script>
      export default {
        name:"CartItem",
        props:["course"],
        data(){
          return {
            options:[ // 有效期
              {value:30,label:"一个月有效"},
              {value:60,label:"二个月有效"},
              {value:90,label:"三个月有效"},
              {value:0,label:"永久有效"},
            ]
          }
        },
        watch:{
          "course.course_expire": function(value){
            // 切换当前课程的有效期
            console.log("有效期:"+value)
          },
          "course.selected": function (value) {
            // 切换当前课程的勾选状态
            console.log("勾选:" + value)
          }
        }
      }
    </script>
    
    <style scoped>
    .cart-item{
      height: 250px;
    }
    .cart-item .el-row{
      height: 100%;
    }
    .course-delete{
        font-size: 14px;
        color: #ffc210;
        cursor: pointer;
    }
    .el-checkbox,.el-select,.course-price,.course-delete{
        display: flex;
        align-items: center;
        justify-content: center;
        height: 100%;
    }
    .el-checkbox{
        padding-top: 55px;
    }
    .el-select{
        padding-top: 45px;
         118px;
        height: 28px;
        font-size: 12px;
        color: #666;
        line-height: 18px;
    }
    .course-info img{
         175px;
        height: 115px;
        margin-right: 35px;
        vertical-align: middle;
    }
    .cart-item .el-col{
        padding: 67px 10px;
        vertical-align: middle!important;
    }
    .course-info{
    
    }
    </style>
    
    
    

    切换勾选状态和课程有效期

    后端提供修改勾选状态的接口

    视图代码:

        def put(self,request):
            """修改购物车中的商品信息"""
            user_id = request.user.id
            course_id = request.data.get("course_id")
            try:
                course_info = Course.objects.get(pk=course_id)
            except:
                return Response({"message": "请求有误,请联系客服"}, status=status.HTTP_507_INSUFFICIENT_STORAGE)
    
            redis = get_redis_connection("cart")
    
            # 操作商品信息之前,必须先确保当前课程在购物车中
            try:
                rs = redis.hget("cart_%s" % user_id, course_id)
                if rs is None:
                    raise Exception
            except:
                return Response({"message": "请求有误,请联系客服"}, status=status.HTTP_507_INSUFFICIENT_STORAGE)
    
            # 修改勾选状态
            selected = request.data.get("selected",None)
            if selected is not None:
                if selected == True:
                    redis.sadd("cart_select_%s" % user_id, course_info.id)
                else:
                    redis.srem("cart_select_%s" % user_id, course_info.id)
    
            # 修改有效期
            course_expire = request.data.get("course_expire",None)
            if course_expire is not None:
                redis.hset("cart_%s" % user_id, course_info.id, course_expire )
    
            return Response({"message":"ok"}, status=status.HTTP_200_OK)
    
    

    CartItem.vue

    <template>
      <div class="cart-item">
              <el-row>
                 <el-col :span="2" class="checkbox"><el-checkbox v-model="course.selected" :checked="course.selected" name="type"></el-checkbox></el-col>
                 <el-col :span="10" class="course-info">
                   <img :src="this.$settings.host+course.course_img" alt="">
                    <span>{{course.name}}</span>
                 </el-col>
                 <el-col :span="4">
                     <el-select v-model="course.course_expire">
                        <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value"></el-option>
                      </el-select>
                 </el-col>
                 <el-col :span="4" class="course-price">¥{{course.price}}</el-col>
                 <el-col :span="4" class="course-delete"><span @click="removeCartHander">删除</span></el-col>
               </el-row>
      </div>
    </template>
    
    <script>
      export default {
        name:"CartItem",
        props:["course"],
        data(){
          return {
            token: localStorage.token || sessionStorage.token,
            user_id: localStorage.user_id || sessionStorage.user_id,
            options:[ // 有效期
              {value:30,label:"一个月有效"},
              {value:60,label:"二个月有效"},
              {value:90,label:"三个月有效"},
              {value:0,label:"永久有效"},
            ]
          }
        },
        methods:{
          removeCartHander(){
            // 从购物车中删除商品信息
            this.$axios.delete(this.$settings.host+"/course/cart/",{
              course_id: this.course.course_id,
            },{
            headers:{
              // 附带已经登录用户的jwt token 提供给后端,一定不能疏忽这个空格
              'Authorization':'JWT '+this.token
            },
          }).then(response=>{
              console.log(response.data)
            }).catch(error=>{
              console.log(error.response)
            });
          },
        },
        watch:{
          "course.course_expire": function(value){
            // 切换当前课程的有效期
            this.$axios.put(this.$settings.host+"/cart/course/",{
              course_id: this.course.course_id,
              course_expire: value
            },{
            headers:{
              // 附带已经登录用户的jwt token 提供给后端,一定不能疏忽这个空格
              'Authorization':'JWT '+this.token
            },
          }).then(response=>{
              console.log(response.data)
            }).catch(error=>{
              console.log(error.response)
            });
          },
          "course.selected": function (value) {
            // 切换当前课程的勾选状态
            this.$axios.put(this.$settings.host+"/cart/course/",{
              course_id: this.course.course_id,
              selected: value
            },{
            headers:{
              // 附带已经登录用户的jwt token 提供给后端,一定不能疏忽这个空格
              'Authorization':'JWT '+this.token
            },
          }).then(response=>{
              console.log(response.data)
            }).catch(error=>{
              console.log(error.response)
            });
          }
        }
      }
    </script>
    
    <style scoped>
    .cart-item{
      height: 250px;
    }
    .cart-item .el-row{
      height: 100%;
    }
    .course-delete{
        font-size: 14px;
        color: #ffc210;
        cursor: pointer;
    }
    .el-checkbox,.el-select,.course-price,.course-delete{
        display: flex;
        align-items: center;
        justify-content: center;
        height: 100%;
    }
    .el-checkbox{
        padding-top: 55px;
    }
    .el-select{
        padding-top: 45px;
         118px;
        height: 28px;
        font-size: 12px;
        color: #666;
        line-height: 18px;
    }
    .course-info img{
         175px;
        height: 115px;
        margin-right: 35px;
        vertical-align: middle;
    }
    .cart-item .el-col{
        padding: 67px 10px;
        vertical-align: middle!important;
    }
    .course-info{
    
    }
    </style>
    
    

    修复添加商品课程到购物车的前端BUG

    用户在课程详情页中退出登录时,如果不刷新页面,则可以继续进行购物。

    出现问题的原因:添加购物车时,判断用户是否登录依靠的是当前组件中data的token数据,而token数据是通过sessionStorage或者localStorage赋值过来的,但是当用户退出登录时,我们删除了sessionStorage或者localStorage,但是并没有删除token值。因为形成了BUG。

    解决方案:退出登录进行页面跳转.或者添加商品课程到购物车时,重新对token赋值。

    logout(){
    
            this.token = false;
            this.user_id=false;
            this.user_name=false;
    
            sessionStorage.removeItem("token");
            sessionStorage.removeItem("user_id");
            sessionStorage.removeItem("user_name");
    
            localStorage.removeItem("token");
            localStorage.removeItem("user_id");
            localStorage.removeItem("user_name");
            let _this = this;
            _this.$alert('退出登录成功!', '路飞学城', {
              callback(){
                _this.$router.push("/");
              }
            });
    
    

    显示购物车商品列表数据

    前端显示购物车页面组件

    <template>
        <div class="cart">
          <Header/>
          <div class="main">
            <div class="cart-title">
              <h3>我的购物车 <span> 共2门课程</span></h3>
            </div>
            <div class="cart-info">
              <el-table :data="courseData" style="100%">
                <el-table-column type="selection" label="" width="87"></el-table-column>
                <el-table-column label="课程" width="540">
                  <template slot-scope="scope">
                    <div class="course-box">
                      <img :src="scope.row.img" alt="">
                      {{scope.row.title}}
                    </div>
                  </template>
                </el-table-column>
                <el-table-column label="有效期" width="216">
                  <template slot-scope="scope">
                    <el-form ref="form" label-width="60px">
                      <el-form-item>
                        <el-select v-model="expire" placeholder="请选择有效期">
                          <el-option v-for="item in expire_list" :key="item.id" :label="item.title" :value="item.id"></el-option>
                        </el-select>
                      </el-form-item>
                    </el-form>
                  </template>
                </el-table-column>
                <el-table-column label="单价" width="162">
                  <template slot-scope="scope">¥{{ scope.row.price }}</template>
                </el-table-column>
                <el-table-column label="操作" width="162">
                  <a href="">删除</a>
                </el-table-column>
              </el-table>
            </div>
            <div class="cart-bottom">
              <div class="select-all"><el-checkbox>全选</el-checkbox></div>
              <div class="delete-any"><img src="../../static/img/ico3.png" alt="">删除</div>
              <div class="cart-bottom-right">
                <span class="total">总计:¥<span>0.0</span></span>
                <span class="go-pay">去结算</span>
              </div>
            </div>
          </div>
          <Footer/>
        </div>
    </template>
    
    <script>
    import Header from "./common/Header"
    import Footer from "./common/Footer"
    export default {
        name: "Cart",
        data(){
          return{
            expire:3,
            expire_list:[
                {title:"一个月有效",id:1},
                {title:"两个月有效",id:2},
                {title:"三个月有效",id:3},
                {title:"永久有效",id:4},
            ],
            courseData:[
              {img:"../../static/course/1544059695.jpeg",title:"课程标题一",expire:"2016",price:"12.00"},
              {img:"../../static/course/1544059695.jpeg",title:"课程标题一",expire:"2016",price:"12.00"},
            ]
          }
        },
        components:{Header,Footer}
    }
    </script>
    
    <style scoped>
    .main{
       1200px;
      margin: 0 auto;
      overflow: hidden; /* 解决body元素和标题之间的上下外边距的塌陷问题 */
    }
    .cart-title h3{
      font-size: 18px;
      color: #666;
      margin: 25px 0;
    }
    .cart-title h3 span{
      font-size: 12px;
      color: #d0d0d0;
      display: inline-block;
    }
    .course-box img{
        max- 175px;
        max-height: 115px;
        margin-right: 35px;
        vertical-align: middle;
    }
    .cart-bottom{
      overflow: hidden;
      height: 80px;
      background: #F7F7F7;
      margin-bottom: 300px;
      margin-top: 50px;
    }
    .select-all{
      float: left;
      margin-right: 58px;
      line-height: 80px;
    }
    .delete-any{
      cursor: pointer;
      float: left;
      line-height: 80px;
    }
    .delete-any img{
      18px;
      height: 18px;
      vertical-align: middle;
      padding-right: 15px;
    }
    .cart-bottom-right{
      float: right;
      text-align: right; /* 文本右对齐 */
    }
    .total{
      margin-right: 62px;
      font-size: 18px;
      color: #666;
    }
    .go-pay{
      outline: none;
      background: #ffc210;
      display: inline-block;
      padding: 27px 50px;
      font-size: 18px;
      cursor: pointer;
      color: #fff;
    }
    </style>
    
    
    

    路由routers/index.js,注册:

    // 导入页面组件
    ...
    import Cart from "../components/Cart"
    
    Vue.use(Router);
    
    export default new Router({
      // 设置路由模式为‘history’,去掉默认的#
      mode: "history",
      routes:[
        // 路由列表
         。。。
          ,{
           name:"Cart",
           path:"/cart",
           component: Cart,
         },
      ]
    })
    
    
    

    后端提供获取购物车课程信息

    from rest_framework.views import APIView
    from courses.models import Course
    from rest_framework.response import Response
    from django_redis import get_redis_connection
    from rest_framework.permissions import IsAuthenticated
    from rest_framework import status
    from django.conf import settings
    class CartAPIView(APIView):
        permission_classes = [IsAuthenticated]
        """购物车视图"""
        def get(self,request):
            """获取购物车商品课程列表"""
            # 获取当前用户ID
            # user_id = 1
            user_id = request.user.id
            # 通过用户ID获取购物车中的商品信息
            redis = get_redis_connection("cart")
            cart_goods_list = redis.hgetall("cart_%s" % user_id ) # 商品课程列表
            cart_goods_selectsfrom rest_framework.views import APIView
    from courses.models import Course
    from rest_framework.response import Response
    from django_redis import get_redis_connection
    from rest_framework.permissions import IsAuthenticated
    from rest_framework import status
    
    
    class CartAPIView(APIView):
        """购物车视图"""
        permission_classes = [IsAuthenticated]
    
        def get(self, request):
            """获取购物车中的所有课程信息"""
    
            # 获取当前登录用户
            # user_id = 1
            user_id = request.user.id
    
            # 通过用户ID,从redis中获取所有的课程信息和勾选状态
            # redis里面的所有数据最终都是以bytes类型的字符串保存的
            redis = get_redis_connection("cart")
            cart_courses_list = redis.hgetall("cart_%s" % user_id)  # 商品课程列表
            cart_courses_selected = redis.smembers("cart_selected_%s" % user_id)
    
            print('++++++++++++++++++++++', cart_courses_list, cart_courses_selected,
                  "++++++++++++++++++++++", sep='
    ')
            """
            ++++++++++++++++++++++
            {b'1': b'-1', b'4': b'-1', b'3': b'-1', b'2': b'-1'}
            {b'3', b'4', b'2'}
            ++++++++++++++++++++++
            """
    
            # 组装数据
            """
               cart_<user_id>:{
                  课程id: 有效期,
                  课程id: 有效期,
                  课程id: 有效期,
               }
               cart_select_<user_id>:{课程id,课程id}
    
               上面两个数据最终要合并到一个数组中,一起返回给客户端
               [
                {
                    course_id:课程id,
                    course_expire:有效期,
                    selected:True/False,  // 勾选状态
                },
               ]
           """
            # 遍历购物车中的商品课程到数据库获取课程的价格, 标题, 图片
            data_list = []
            try:
                for course_id_bytes, expire_bytes in cart_courses_list.items():
                    course_id = int(course_id_bytes.decode())
                    expire = expire_bytes.decode()
                    course = Course.objects.get(pk=course_id)
                    data_list.append({
                        "id": course_id,
                        "expire": expire,
                        "course_img": course.course_img.url,
                        "name": course.name,
                        "price": course.get_course_price(),
                        "is_select": course_id_bytes in cart_courses_selected
                    })
            except:
                pass
    
            # 返回客户端
            print(data_list)
            return Response(data_list, status=status.HTTP_200_OK) = redis.smembers("cart_selected_%s" % user_id)
            # redis里面的所有数据最终都是以bytes类型的字符串保存的
            # print( cart_goods_selects ) # 格式: {b'7', b'3', b'5'}
            # print( cart_goods_list ) # 格式: {b'7': b'-1', b'5': b'-1'}
            # 遍历购物车中的商品课程到数据库获取课程的价格, 标题, 图片
            data_list = []
            try:
                for course_id_bytes,expire_bytes in cart_goods_list.items():
                    course_id = int( course_id_bytes.decode() )
                    expire    = expire_bytes.decode()
                    course = Course.objects.get(pk=course_id)
                    data_list.append({
                        "id": course_id,
                        "expire":expire,
                        "course_img": course.course_img.url,
                        "name": course.name,
                        "price": course.get_course_price(),
                        "is_select": course_id_bytes in cart_goods_selects
                    })
            except:
                return Response(data_list,status=status.HTTP_500_INTERNAL_SERVER_ERROR)
            # print(data_list)
            # 返回查询结果
            return Response(data_list,status=status.HTTP_200_OK)
    
    

    前端请求显示课程信息

    Cart.vue,代码:

    <template>
      <div class="cart">
        <Header/>
        <div class="main">
          <div class="cart-title">
            <h3>我的购物车 <span> 共{{$store.state.cart.count}}门课程</span></h3>
          </div>
          <div class="cart-info">
            <el-table
              :data="courseData"
              style="100%"
              ref="multipleTable"
              @select="currentSelected"
            >
              <el-table-column type="selection" width="87"></el-table-column>
              <el-table-column label="课程" width="540">
                <template slot-scope="scope">
                  <div class="course-box">
                    <img :src="$settings.Host + scope.row.course_img" alt="">
                    {{scope.row.name}}
                  </div>
                </template>
              </el-table-column>
              <el-table-column label="有效期" width="216">
                <template slot-scope="scope">
                  <el-select @change="changeExpire(scope.row)" v-model="scope.row.expire" placeholder="请选择">
                    <el-option v-for="item in expire_list" :key="item.id" :label="item.title" :value="item.id"></el-option>
                  </el-select>
                </template>
              </el-table-column>
              <el-table-column label="单价" width="162">
                <template slot-scope="scope">¥{{ scope.row.price.toFixed(2) }}</template>
              </el-table-column>
              <el-table-column label="操作" width="162">
                <template slot-scope="scope">
                  <a @click="cartDel(scope.row, scope.row.name)">删除</a>
                </template>
              </el-table-column>
            </el-table>
          </div>
          <div class="cart-bottom">
            <div class="select-all">
              <el-checkbox>全选</el-checkbox>
            </div>
            <div class="delete-any"><img src="" alt="">删除</div>
            <div class="cart-bottom-right">
              <span class="total">总计:¥<span>0.0</span></span>
              <span class="go-pay">去结算</span>
            </div>
          </div>
        </div>
        <Footer/>
      </div>
    </template>
    
    <script>
      import Header from "./common/Header"
      import Footer from "./common/Footer"
    
      export default {
        name: "Cart",
        data() {
          return {
            expire: 3,
            expire_list: [
              {title: "一个月有效", id: 1},
              {title: "两个月有效", id: 2},
              {title: "三个月有效", id: 3},
              {title: "永久有效", id: -1},
            ],
            courseData: []
          }
        },
        components: {Header, Footer},
        created(){
          // 判断是否登录
          this.token = sessionStorage.token || localStorage.token;
          if(!this.token){
            this.$confirm("对不起,您尚未登录!请登录", "Attention").then(()=>{
              this.$router.push("/login");
            }).catch(()=>{
              this.$router.go(-1);
            })
          }else{
            //  获取购物车商品数据
            this.$axios.get(this.$settings.Host+"/cart/course/", {
              headers: {
                // 注意空格
                "Authorization": "jwt " + this.token
              }
            }).then(response=>{
              this.courseData = response.data;
              console.log("courseData",response.data);
    
              // 更新在vuex中的数据
              this.$store.state.cart.count = response.data.length;
             //  setTimeout(()=>{
             //    let text_expire_list = [];
             //    for(let i=0; i<this.expire_list.length; i++){
             //      text_expire_list[this.expire_list[i].id] = this.expire_list[i].title;
             //
             //    }
             //    console.log(text_expire_list);
             //
             //    for(let i=0; i< this.courseData.length; i++){
             //      // 设置选中效果
             //      this.$refs.multipleTable.toggleRowSelection(this.courseData[i],
             //        this.courseData[i].is_select);
             //
             //      // 修改有效期显示值
             //      this.courseData[i].expire = text_expire_list[this.courseData[i].expire];
             //    }
             //  }, 0)
              // 调整因为ajax数据请求导致勾选状态人没有出现的原因,使用定时器进行延时调用
              setTimeout(()=>{
                let expire_data = [];
                this.expire_list.forEach(row=>{
                  expire_data[row.id] = row.title;
                });
                console.log("expire_data", expire_data);
    
                // row 就是字典数据[json]
               this.courseData.forEach(row=>{
                 if(row.is_select){
                   this.$refs.multipleTable.toggleRowSelection(row);
                 }
    
                 // 调整有效期选项中数值变成文本内容
                 row.expire = expire_data[row.expire];
               })
              }, 0)
            }).catch(error=>{
              console.log(error.response);
              let status = error.response.status;
              if(status === 401){
                this.token = null;
                sessionStorage.removeItem("token");
                localStorage.removeItem("token");
                let _this = this;
                this.$alert("您尚未登录或登录超时!请重新登录", 'Warning', {
                  callback(){
                    _this.$router.push("/login");
                  }
                })
              }
            })
          }
        },
    
        methods: {},
    
      }
    </script>
    
    

    修复商品课程的默认选中和有效期的文本显示效果

    <template>
      <div class="cart">
        <Header/>
        <div class="main">
          <div class="cart-title">
            <h3>我的购物车 <span> 共{{$store.state.cart.count}}门课程</span></h3>
          </div>
          <div class="cart-info">
            <el-table
              :data="courseData"
              style="100%"
              ref="multipleTable"
              @select="currentSelected"
            >
              <el-table-column type="selection" width="87"></el-table-column>
              <el-table-column label="课程" width="540">
                <template slot-scope="scope">
                  <div class="course-box">
                    <img :src="$settings.Host + scope.row.course_img" alt="">
                    {{scope.row.name}}
                  </div>
                </template>
              </el-table-column>
              <el-table-column label="有效期" width="216">
                <template slot-scope="scope">
                  <el-select @change="changeExpire(scope.row)" v-model="scope.row.expire" placeholder="请选择">
                    <el-option v-for="item in expire_list" :key="item.id" :label="item.title" :value="item.id"></el-option>
                  </el-select>
                </template>
              </el-table-column>
              <el-table-column label="单价" width="162">
                <template slot-scope="scope">¥{{ scope.row.price.toFixed(2) }}</template>
              </el-table-column>
              <el-table-column label="操作" width="162">
                <template slot-scope="scope">
                  <a @click="cartDel(scope.row, scope.row.name)">删除</a>
                </template>
              </el-table-column>
            </el-table>
          </div>
          <div class="cart-bottom">
            <div class="select-all">
              <el-checkbox>全选</el-checkbox>
            </div>
            <div class="delete-any"><img src="" alt="">删除</div>
            <div class="cart-bottom-right">
              <span class="total">总计:¥<span>0.0</span></span>
              <span class="go-pay">去结算</span>
            </div>
          </div>
        </div>
        <Footer/>
      </div>
    </template>
    
    <script>
      import Header from "./common/Header"
      import Footer from "./common/Footer"
    
      export default {
        name: "Cart",
        data() {
          return {
            expire: 3,
            expire_list: [
              {title: "一个月有效", id: 1},
              {title: "两个月有效", id: 2},
              {title: "三个月有效", id: 3},
              {title: "永久有效", id: -1},
            ],
            courseData: []
          }
        },
        components: {Header, Footer},
        created(){
          // 判断是否登录
          this.token = sessionStorage.token || localStorage.token;
          if(!this.token){
            this.$confirm("对不起,您尚未登录!请登录", "Attention").then(()=>{
              this.$router.push("/login");
            }).catch(()=>{
              this.$router.go(-1);
            })
          }else{
            //  获取购物车商品数据
            this.$axios.get(this.$settings.Host+"/cart/course/", {
              headers: {
                // 注意空格
                "Authorization": "jwt " + this.token
              }
            }).then(response=>{
              this.courseData = response.data;
              console.log("courseData",response.data);
    
              // 更新在vuex中的数据
              this.$store.state.cart.count = response.data.length;
             //  setTimeout(()=>{
             //    let text_expire_list = [];
             //    for(let i=0; i<this.expire_list.length; i++){
             //      text_expire_list[this.expire_list[i].id] = this.expire_list[i].title;
             //
             //    }
             //    console.log(text_expire_list);
             //
             //    for(let i=0; i< this.courseData.length; i++){
             //      // 设置选中效果
             //      this.$refs.multipleTable.toggleRowSelection(this.courseData[i],
             //        this.courseData[i].is_select);
             //
             //      // 修改有效期显示值
             //      this.courseData[i].expire = text_expire_list[this.courseData[i].expire];
             //    }
             //  }, 0)
              // 调整因为ajax数据请求导致勾选状态人没有出现的原因,使用定时器进行延时调用
              setTimeout(()=>{
                let expire_data = [];
                this.expire_list.forEach(row=>{
                  expire_data[row.id] = row.title;
                });
                console.log("expire_data", expire_data);
    
                // row 就是字典数据[json]
               this.courseData.forEach(row=>{
                 if(row.is_select){
                   this.$refs.multipleTable.toggleRowSelection(row);
                 }
    
                 // 调整有效期选项中数值变成文本内容
                 row.expire = expire_data[row.expire];
               })
              }, 0)
            }).catch(error=>{
              console.log(error.response);
              let status = error.response.status;
              if(status === 401){
                this.token = null;
                sessionStorage.removeItem("token");
                localStorage.removeItem("token");
                let _this = this;
                this.$alert("您尚未登录或登录超时!请重新登录", 'Warning', {
                  callback(){
                    _this.$router.push("/login");
                  }
                })
              }
            })
          }
        },
    
        methods: {},
    
      }
    </script>
    
    

    切换勾选状态

    后端提供修改勾选状态的接口

    视图代码:

    from django.shortcuts import render
    
    # Create your views here.
    from rest_framework.views import APIView
    from courses.models import Course
    from rest_framework.response import Response
    from django_redis import get_redis_connection
    from rest_framework.permissions import IsAuthenticated
    from rest_framework import status
    
    
    class CartAPIView(APIView):
        """购物车视图"""
        # permission_classes = [IsAuthenticated]
    
        def get(self, request):
            """获取购物车中的所有课程信息"""
            ......
            return Response(data_list, status=status.HTTP_200_OK)
    
        def post(self, request):
            """购物车添加商品"""
            ......
            return Response({"message": "成功添加课程到购物车",
                             "count": count,
                             }, status=status.HTTP_200_OK)
    
        def put(self, request):
            """修改购物车中商品的信息"""
            # 获取当前登录用户ID
            user_id = request.user.id
    
            # 接受课程ID,判断课程ID是否存在
            course_id = request.data.get("course_id")
            try:
                Course.objects.get(pk=course_id, is_delete=False, is_show=True)
            except:
                return Response({"message": "请求有误"}, status=status.HTTP_400_BAD_REQUEST)
    
            redis = get_redis_connection('cart')
    
            # 操作商品信息之前,必须先确保当前课程在购物车中
            try:
                rs = redis.hget("cart_%s" % user_id, course_id)
                if rs is None:
                    raise Exception
            except:
                return Response({"message": "请求有误,请联系客服"}, status=status.HTTP_507_INSUFFICIENT_STORAGE)
    
            # 获取勾选状态
            is_select = request.data.get("is_select")
    
            # 链接redis
            redis = get_redis_connection('cart')
    
            # 修改购物车中指定的商品课程的信息
            if is_select:
                # 从勾选set中增加一个课程ID
                redis.sadd("cart_selected_%s" % user_id, course_id)
            else:
                redis.srem("cart_selected_%s" % user_id, course_id)
    
            return Response({"message": "Okay!"},
                            status=status.HTTP_200_OK)
    
    

    前端发送更新勾选状态的请求

    template代码:

              <el-table
                :data="courseData"
                style="100%"
                ref="multipleTable"
                @select="currentSelected"
              >
    
    

    script新增一个 操作方法:

      methods: {
          // 切换课程勾选状态
          currentSelected(selection, row){
            // selection 表示所有被勾选的信息
            // row 当前操作的数据
            let is_select = true;
            if(selection.indexOf(row)===-1){
              is_select = false;
            }
    
            // 获取当前课程ID
            let course_id = row.id;
    
            // 发送put请求,切换勾选状态
            this.$axios.put(this.$settings.Host+"/cart/course/", {
              course_id: course_id,
              is_select: is_select,
            }, {
               headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              },
            }).then(response=>{
              this.$message(response.data.message, "Attention");
            }).catch(error=>{
              console.log(error.response);
            })
          },
        }
    
    

    课程有效期

    后端提供修改勾选状态的接口

    因为前面实现修改购物车商品课程的勾选状态已经使用put方法提供API接口了,所以我们现在要修改课程有效期,业务上来说也是更新购物车中商品信息,所以我们可以继续在put里面通过判断是否有expire参数来执行不同代码,也可以使用http的patch操作来完成更新课程有效期的功能。

    我们这里使用patch方法。

        def patch(self,request):
            """更新购物城中的商品信息"""
            # 获取当前登录的用户ID
            # user_id = 1
            user_id = request.user.id
    
            # 获取当前操作的课程ID
            course_id = request.data.get("course_id")
    
            # 获取新的有效期
            expire = request.data.get("expire")
    
            # 获取redis链接
            redis = get_redis_connection("cart")
    
            # 更新购物中商品课程的有效期
            redis.hset("cart_%s" % user_id,course_id, expire)
    
            return Response({
                "message": "修改购物车信息成功!"
            }, status=status.HTTP_200_OK)
    
    
    前端提交修改商品课程的有效期请求
    <template>
      <div class="cart">
        <Header/>
        <div class="main">
          <div class="cart-title">
            <h3>我的购物车 <span> 共{{$store.state.cart.count}}门课程</span></h3>
          </div>
          <div class="cart-info">
            <el-table
              :data="courseData"
              style="100%"
              ref="multipleTable"
              @select="currentSelected"
            >
              <el-table-column type="selection" width="87"></el-table-column>
              <el-table-column label="课程" width="540">
                <template slot-scope="scope">
                  <div class="course-box">
                    <img :src="$settings.Host + scope.row.course_img" alt="">
                    {{scope.row.name}}
                  </div>
                </template>
              </el-table-column>
              <el-table-column label="有效期" width="216">
                <template slot-scope="scope">
                  <el-select @change="changeExpire(scope.row)" v-model="scope.row.expire" placeholder="请选择">
                    <el-option v-for="item in expire_list" :key="item.id" :label="item.title" :value="item.id"></el-option>
                  </el-select>
                </template>
              </el-table-column>
              <el-table-column label="单价" width="162">
                <template slot-scope="scope">¥{{ scope.row.price.toFixed(2) }}</template>
              </el-table-column>
              <el-table-column label="操作" width="162">
                <template slot-scope="scope">
                  <a @click="CartDel(scope.row.id,scope.row.name)">删除</a>
                </template>
              </el-table-column>
            </el-table>
          </div>
          <div class="cart-bottom">
            <div class="select-all">
              <el-checkbox>全选</el-checkbox>
            </div>
            <div class="delete-any"><img src="" alt="">删除</div>
            <div class="cart-bottom-right">
              <span class="total">总计:¥<span>0.0</span></span>
              <span class="go-pay">去结算</span>
            </div>
          </div>
        </div>
        <Footer/>
      </div>
    </template>
    
    <script>
      import Header from "./common/Header"
      import Footer from "./common/Footer"
    
      export default {
        name: "Cart",
        data() {
          return {
            expire: 3,
            expire_list: [
              {title: "一个月有效", id: 1},
              {title: "两个月有效", id: 2},
              {title: "三个月有效", id: 3},
              {title: "永久有效", id: -1},
            ],
            courseData: []
          }
        },
        components: {Header, Footer},
        created(){......},
    
        methods: {
          // 切换课程勾选状态
          currentSelected(selection, row){......},
    
          // 切换课程的有效期
          changeExpire(course){
            let course_id = course.id;
            let expire = course.expire;
    
            // 发送patch请求更新有效期
            this.$axios.patch(this.$settings.Host+"/cart/course/", {
              course_id: course_id,
              expire,  // expire <==> expire: expire,
            }, {
              headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              },
            }).then(response=>{
              this.$message(response.data.message, "Attention");
            }).catch(error=>{
              console.log(error.response);
            })
          }
        },
    
      }
    </script>
    
    

    删除购物车中的商品信息

    后端提供从购物车中删除商品课程的API接口

        def delete(self,request):
            """从购物车中删除数据"""
            # 获取当前登录用户ID
            # user_id = 1
            user_id = request.user.id
            # 获取课程ID
            course_id = request.query_params.get("course_id")
    
            redis = get_redis_connection("cart")
            pipeline = redis.pipeline()
    
            pipeline.multi()
            # 从购物车中删除指定商品课程
            pipeline.hdel("cart_%s" % user_id, course_id)
    
            # 从勾选集合中移除指定商品课程
            pipeline.srem("cart_selected_%s" % user_id, course_id )
    
            pipeline.execute()
    
            # 返回操作结果
            return Response({"message":"删除商品课程成功!"},status=status.HTTP_204_NO_CONTENT)
    
    

    前端请求删除商品课程

    tempalte,代码:

                  <template slot-scope="scope">
                    <a @click="CartDel(scope.row,scope.row.name)">删除</a>
                  </template>
    
    

    script标签代码:

    methods: {
          // 切换课程勾选状态
          currentSelected(selection, row){......},
    
          // 切换课程的有效期
          changeExpire(course){.....},
    
           // 删除课程
          cartDel(course, course_name){
            this.$confirm(`您确定要从购物车删除《${course_name}》`, "Attention").then(()=>{
              let course_id = course.id;
    
              // 发送请求
              this.$axios.delete(this.$settings.Host+"/cart/course/", {
                params: {
                  course_id: course_id,
                },
                headers: {
                   // 注意下方的空格!!!
                  "Authorization":"jwt " + this.token
                },
              }).then(response=>{
                let index = this.courseData.indexOf(course);
                this.courseData.splice(index, 1);
                console.log("courseData", this.courseData);
                this.$message("删除成功!")
              }).catch(error=>{
                console.log(error.response);
              });
            }).catch(()=>{
              // 取消操作
            })
          },
        },
    
      }
    
    

    购物车的价格统计

    <template>
        <div class="cart">
          <Header/>
          <div class="main">
            <div class="cart-title">
              <h3>我的购物车 <span> 共2门课程</span></h3>
            </div>
            <div class="cart-info">
              <el-table
                :data="courseData"
                style="100%"
                ref="multipleTable"
                @select="currentSelected"
                @selection-change="SelectionChange"
              >
                <el-table-column type="selection" width="87"></el-table-column>
                <el-table-column label="课程" width="540">
                  <template slot-scope="scope">
                    <div class="course-box">
                      <img :src="$settings.Host + scope.row.course_img" alt="">
                      <router-link :to="'/detail?id='+scope.row.id">{{scope.row.name}}</router-link>
                    </div>
                  </template>
                </el-table-column>
                <el-table-column label="有效期" width="216">
                  <template slot-scope="scope">
                    <el-select @change="ChangeExpire(scope.row)" v-model="scope.row.expire" placeholder="请选择">
                      <el-option v-for="item in expire_list" :key="item.id" :label="item.title" :value="item.id"></el-option>
                    </el-select>
                  </template>
                </el-table-column>
                <el-table-column label="单价" width="162">
                  <template slot-scope="scope">¥{{ scope.row.price.toFixed(2) }}</template>
                </el-table-column>
                <el-table-column label="操作" width="162">
                  <template slot-scope="scope">
                    <a @click="CartDel(scope.row,scope.row.name)">删除</a>
                  </template>
                </el-table-column>
              </el-table>
            </div>
            <div class="cart-bottom">
              <div class="select-all"><el-checkbox>全选</el-checkbox></div>
              <div class="delete-any"><img src="../../static/img/ico3.png" alt="">删除</div>
              <div class="cart-bottom-right">
                <span class="total">总计:¥<span>{{total_price}}</span></span>
                <span class="go-pay">去结算</span>
              </div>
            </div>
          </div>
          <Footer/>
        </div>
    </template>
    
    <script>
    import Header from "./common/Header"
    import Footer from "./common/Footer"
    export default {
        name: "Cart",
        data(){
          return{
            expire:3,
            expire_list:[
                {title:"一个月有效",id:1},
                {title:"两个月有效",id:2},
                {title:"三个月有效",id:3},
                {title:"永久有效",id:-1},
            ],
            courseData:[], // 购物车中的商品信息
            selection:[],  // 购物车中被勾选的商品信息
            total_price:0.00,
          }
        },
        watch:{
          selection(){
            // 当课程勾选状态发生变化时核算价格
            this.getTotalPrice();
          },
          courseData(){
            // 当课程数量发生变化时核算价格
            this.getTotalPrice();
          },
        },
        created(){
          // 判断是否登录
          this.token = sessionStorage.token || localStorage.token;
          if( !this.token ){
            this.$confirm("对不起,您尚未登录!请登录",'提示').then(() => {
              this.$router.push("/login");
            }).catch(()=>{
              this.$router.go(-1);
            });
          }else{
            // 获取购物车商品数据
            this.$axios.get(this.$settings.Host+"/carts/course/",{
              headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              }
            }).then(response=>{
    
              this.courseData = response.data;
              // 更新在vuex里面的数据
              this.$store.state.cart.count = response.data.length;
    
              // 调整因为ajax数据请求导致勾选状态人没有出现的原因,使用定时器进行延时调用
              setTimeout(()=>{
                let expire_data = [];
                this.expire_list.forEach(row=>{
                  expire_data[row.id] = row.title;
                });
    
                // row 就是字典数据[json]
                this.courseData.forEach(row => {
                  // 设置商品课程的选中状态
                  if(row.is_select){
                    this.$refs.multipleTable.toggleRowSelection(row);
                  }
    
                  // 调整有效期选项中数值变成文本内容
                  row.expire = expire_data[row.expire];
                });
              },0)
    
            }).catch(error=>{
              let status = error.response.status;
              if( status == 401 ){
                this.token = null;
                sessionStorage.removeItem("token");
                localStorage.removeItem("token");
                let _this = this;
                this.$alert("您尚未登录或登录超时!请重新登录","警告",{
                  callback(){
                    _this.$router.push("/login");
                  }
                });
              }
            })
    
          }
        },
        methods:{
          getTotalPrice(){
            // 核算购物车中所有勾选商品的总价格
            let total = 0;
            this.selection.forEach(row=>{
              total += row.price;
            });
            // 保留2个小数位
            this.total_price = total.toFixed(2);
          },
          CartDel(course,course_name){
            this.$confirm(`您确定要从购物车删除<<${course_name}>>这个课程么?`,"提示!").then(()=>{
              let course_id = course.id;
              // 发送请求
              this.$axios.delete(this.$settings.Host+"/carts/course/",{
                params:{
                  course_id:course_id,
                },
                headers:{
                  // 注意下方的空格!!!
                  "Authorization":"jwt " + this.token
                },
              }).then(response=>{
                let index = this.courseData.indexOf(course);
                this.courseData.splice(index,1);
                this.$message("删除成功!");
    
              }).catch(error=>{
                console.log(error.response);
              });
    
            }).catch(()=>{
              // 取消操作
    
            });
          },
          currentSelected(selection,row){
            // selection 表示所有被勾选的信息
            // row 当前操作的数据
            let is_select = true;
            if( selection.indexOf(row) == -1 ){
              is_select = false;
            }
    
            // 获取当前课程ID
            let course_id = row.id;
            // 切换勾选状态
    
            // 发送请求
            this.$axios.put(this.$settings.Host+"/carts/course/",{
              course_id: course_id,
              is_select: is_select,
            },{
              headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              },
            }).then(response=>{
    
              this.$message(response.data.message,"提示");
            }).catch(error=>{
    
              console.log(error.response)
            })
          },
          // 更新课程的有效期
          ChangeExpire(course){
            // 获取课程ID和有效期
            let course_id = course.id;
            let expire    = course.expire
            // 发送patch请求更新有效期
            this.$axios.patch(this.$settings.Host+"/carts/course/",{
              course_id,
              expire,  // 这里是简写,相当于 expire:expire,
            },{
              headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              },
            }).then(response=>{
              this.$message(response.data.message,"提示");
            });
          },
          // 获取勾选过的商品课程列表
          SelectionChange(data){
            this.selection = data;
          }
        },
        components:{Header,Footer}
    }
    </script>
    
    

    显示当前课程所属的真实价格

    价格策略模型

    价格优惠活动类型名称: 限时免费, 限时折扣, 限时减免, 积分抵扣, 满减, 优惠券
    公式:
    限时免费      原价-原价
    限时折扣      原价*0.8
    限时减免      原价-减免价
    积分抵扣      原价-(积分计算后换算价格) ->> 积分换算比率
    满减         原价-(满减计算后换算价格)  
    优惠券       原价-优惠券价格         -->> 优惠券
    
    

    模型代码:

    from django.db import models
    from luffy.utils.models import BaseModel
    from datetime import datetime
    from decimal import Decimal
    # Create your models here.
    class CourseCategory(BaseModel):
        """
        课程分类
        """
        name = models.CharField(max_length=64, unique=True, verbose_name="分类名称")
        class Meta:
            db_table = "ly_course_category"
            verbose_name = "课程分类"
            verbose_name_plural = "课程分类"
    
        def __str__(self):
            return "%s" % self.name
    
    
    from ckeditor_uploader.fields import RichTextUploadingField
    class Course(BaseModel):
        """
        专题课程
        """
        course_type = (
            (0, '付费'),
            (1, 'VIP专享'),
            (2, '学位课程')
        )
        level_choices = (
            (0, '初级'),
            (1, '中级'),
            (2, '高级'),
        )
        status_choices = (
            (0, '上线'),
            (1, '下线'),
            (2, '预上线'),
        )
        name = models.CharField(max_length=128, verbose_name="课程名称")
        course_img = models.ImageField(upload_to="course", max_length=255, verbose_name="封面图片", blank=True, null=True)
        course_type = models.SmallIntegerField(choices=course_type,default=0, verbose_name="付费类型")
        # 使用这个字段的原因
        video = models.FileField(upload_to="video", null=True,blank=True,default=None, verbose_name="封面视频")
        brief = RichTextUploadingField(max_length=2048, verbose_name="详情介绍", null=True, blank=True)
        level = models.SmallIntegerField(choices=level_choices, default=1, verbose_name="难度等级")
        pub_date = models.DateField(verbose_name="发布日期", auto_now_add=True)
        period = models.IntegerField(verbose_name="建议学习周期(day)", default=7)
        attachment_path = models.FileField(max_length=128, verbose_name="课件路径", blank=True, null=True)
        status = models.SmallIntegerField(choices=status_choices, default=0, verbose_name="课程状态")
        course_category = models.ForeignKey("CourseCategory", on_delete=models.CASCADE, null=True, blank=True,verbose_name="课程分类")
        students = models.IntegerField(verbose_name="学习人数",default = 0)
        lessons = models.IntegerField(verbose_name="总课时数量",default = 0)
        pub_lessons = models.IntegerField(verbose_name="课时更新数量",default = 0)
        price = models.DecimalField(max_digits=6,decimal_places=2, verbose_name="课程原价",default=0)
        teacher = models.ForeignKey("Teacher",on_delete=models.DO_NOTHING, null=True, blank=True,verbose_name="授课老师")
        class Meta:
            db_table = "ly_course"
            verbose_name = "专题课程"
            verbose_name_plural = "专题课程"
    
        def __str__(self):
            return "%s" % self.name
    
        def get_course_discount_type(self):
            now = datetime.now()
            try:
                course_prices = self.prices.get(start_time__lte=now, end_time__gte=now, is_delete=False, is_show=True)
                # 获取优惠活动类型
                return course_prices.discount.discount_type.name
            except:
                return ""
    
        def get_course_price(self):
            # 获取当前课程的真实价格
            # 获取当前课程的价格策略
    
            now = datetime.now()
            try:
                course_prices = self.prices.get( start_time__lte=now,end_time__gte=now, is_delete=False,is_show=True)
    
                # 价格优惠条件判断,原价大于优惠条件才参与活动
                if self.price < course_prices.discount.condition:
                    return self.price
    
                # 当优惠公式为多行文本,则表示满减
                if course_prices.discount.sale[0]=="满":
                    sale_list = course_prices.discount.sale.split("
    ")
                    sale_price_list = []
                    # 通过遍历提取所有策略项的优惠价格值
                    for sale_item in sale_list:
                        sale = int( sale_item[1: sale_item.index("-")] )
                        sele_price = int( sale_item[sale_item.index("-")+1:] )
                        if self.price >= sale:
                            sale_price_list.append( sele_price )
    
                    # 当前课程只能享受一个最大优惠
                    return self.price - max( sale_price_list )
    
                # 当优惠公式为-1,则表示真实价格为0
                if course_prices.discount.sale == "-1":
                    return 0
    
                # 当优惠公式为*开头,则表示折扣
                if course_prices.discount.sale[0] == "*":
                    sale = Decimal( course_prices.discount.sale[1:] )
                    return self.price * sale
    
                # 当优惠公式为负数,则表示减免
                if course_prices.discount.sale[0] == "-":
                    sale = Decimal( course_prices.discount.sale[1:] )
                    real_price = self.price - sale
                    return real_price if real_price > 0 else 0
    
            except:
                print("---没有优惠---")
    
            return self.price
    
        def lesson_list(self):
            """获取当前课程的前8个课时展示到列表中"""
    
            # 获取所有章节
            chapters_list = self.coursechapters.filter(is_delete=False,is_show=True)
            lesson_list = []
            if chapters_list:
                for chapter in chapters_list:
                    lessons = chapter.coursesections.filter(is_delete=False,is_show=True)[:4]
                    if lessons:
                        for lesson in lessons:
                            lesson_list.append({
                                "id":lesson.id,
                                "name":lesson.name,
                                "free_trail":lesson.free_trail
                            })
    
            return lesson_list[:4]
    
        def course_level(self):
            """把课程难度数值转换成文本"""
            return self.level_choices[self.level][1]
    
    class Teacher(BaseModel):
        """讲师、导师表"""
        role_choices = (
            (0, '讲师'),
            (1, '导师'),
            (2, '班主任'),
        )
        name = models.CharField(max_length=32, verbose_name="讲师title")
        role = models.SmallIntegerField(choices=role_choices, default=0, verbose_name="讲师身份")
        title = models.CharField(max_length=64, verbose_name="职位、职称")
        signature = models.CharField(max_length=255, verbose_name="导师签名", help_text="导师签名", blank=True, null=True)
        image = models.ImageField(upload_to="teacher", null=True, blank=True, verbose_name = "讲师封面")
        brief = models.TextField(max_length=1024, verbose_name="讲师描述")
    
        class Meta:
            db_table = "ly_teacher"
            verbose_name = "讲师导师"
            verbose_name_plural = "讲师导师"
    
        def __str__(self):
            return "%s" % self.name
    
    
    class CourseChapter(BaseModel):
        """课程章节"""
        course = models.ForeignKey("Course", related_name='coursechapters', on_delete=models.CASCADE, verbose_name="课程名称")
        chapter = models.SmallIntegerField(verbose_name="第几章", default=1)
        name = models.CharField(max_length=128, verbose_name="章节标题")
        summary = models.TextField(verbose_name="章节介绍", blank=True, null=True)
        pub_date = models.DateField(verbose_name="发布日期", auto_now_add=True)
    
        class Meta:
            db_table = "ly_course_chapter"
            verbose_name = "课程章节"
            verbose_name_plural = "课程章节"
    
        def __str__(self):
            return "%s:(第%s章)%s" % (self.course, self.chapter, self.name)
    
    
    class CourseLesson(BaseModel):
        """课程课时"""
        section_type_choices = (
            (0, '文档'),
            (1, '练习'),
            (2, '视频')
        )
        chapter = models.ForeignKey("CourseChapter", related_name='coursesections', on_delete=models.CASCADE,verbose_name="课程章节")
        name = models.CharField(max_length=128,verbose_name = "课时标题")
        orders = models.PositiveSmallIntegerField(verbose_name="课时排序")
        section_type = models.SmallIntegerField(default=2, choices=section_type_choices, verbose_name="课时种类")
        section_link = models.CharField(max_length=255, blank=True, null=True, verbose_name="课时链接", help_text = "若是video,填vid,若是文档,填link")
        duration = models.CharField(verbose_name="视频时长", blank=True, null=True, max_length=32)  # 仅在前端展示使用
        pub_date = models.DateTimeField(verbose_name="发布时间", auto_now_add=True)
        free_trail = models.BooleanField(verbose_name="是否可试看", default=False)
    
        class Meta:
            db_table = "ly_course_lesson"
            verbose_name = "课程课时"
            verbose_name_plural = "课程课时"
    
        def __str__(self):
            return "%s-%s" % (self.chapter, self.name)
    
    """价格相关的模型"""
    class PriceDiscountType(BaseModel):
        """课程优惠类型"""
        name = models.CharField(max_length=32, verbose_name="类型名称")
        remark = models.CharField(max_length=250,blank=True, null=True, verbose_name="备注信息")
    
        class Meta:
            db_table = "ly_price_discount_type"
            verbose_name = "课程优惠类型"
            verbose_name_plural = "课程优惠类型"
    
        def __str__(self):
            return "%s" % (self.name)
    
    class PriceDiscount(BaseModel):
        """课程优惠模型"""
        discount_type = models.ForeignKey("PriceDiscountType",on_delete=models.CASCADE, related_name='pricediscounts',verbose_name="优惠类型")
        discount_name = models.CharField(max_length=150,verbose_name="优惠活动名称")
        condition     = models.IntegerField(blank=True,default=0,verbose_name="满足优惠的价格条件")
        sale          = models.TextField(verbose_name="优惠公式",help_text="""
        -1表示免费;<br>
        *号开头表示折扣价,例如*0.82表示八二折;<br>
        $号开头表示积分兑换,例如$50表示可以兑换50积分<br>
        表示满减,则需要使用 原价-优惠价格,例如表示,课程价格大于100,优惠10;大于200,优惠20,格式如下:<br>
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;满100-10<br>
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;满200-20<br>
               
        """)
    
        class Meta:
            db_table = "ly_price_discount"
            verbose_name = "价格优惠策略"
            verbose_name_plural = "价格优惠策略"
    
        def __str__(self):
            return "价格优惠:%s,优惠条件:%s,优惠值:%s" % (self.discount_type.name,self.condition,self.sale)
    
    class CoursePriceDiscount(BaseModel):
        """课程与优惠策略的关系表"""
        course = models.ForeignKey("Course",on_delete=models.CASCADE, related_name="prices",verbose_name="课程")
        discount = models.ForeignKey("PriceDiscount",on_delete=models.CASCADE,related_name="courses",verbose_name="优惠活动")
        start_time = models.DateTimeField(verbose_name="优惠策略的开始时间")
        end_time = models.DateTimeField(verbose_name="优惠策略的结束时间")
    
        class Meta:
            db_table = "ly_course_price_dicount"
            verbose_name="课程与优惠策略的关系表"
            verbose_name_plural="课程与优惠策略的关系表"
    
        def __str__(self):
            return "优惠: %s,开始时间:%s,结束时间:%s" % (self.discount.discount_name, self.start_time,self.end_time)
    
    

    执行数据迁移

    python manage.py makemigrations
    python manage.py migrate
    
    

    添加测试数据

    1558342289388

    后端在模型中计算课程真实价格

    因为课程的优惠是具有时效性的,所以我们计算价格的时候需要先判断当前优惠是否过期了。

    settings/dev.py,代码:

    USE_TZ = False
    
    

    courses/models.py,代码:

    from django.db import models
    from luffy.utils.models import BaseModel
    from datetime import datetime
    from decimal import Decimal
    # Create your models here.
    class CourseCategory(BaseModel):
        """
        课程分类
        """
        。。。
    
    
    from ckeditor_uploader.fields import RichTextUploadingField
    class Course(BaseModel):
        """
        专题课程
        """
        course_type = (
            (0, '付费'),
            (1, 'VIP专享'),
            (2, '学位课程')
        )
        level_choices = (
            (0, '初级'),
            (1, '中级'),
            (2, '高级'),
        )
        status_choices = (
            (0, '上线'),
            (1, '下线'),
            (2, '预上线'),
        )
        name = models.CharField(max_length=128, verbose_name="课程名称")
        course_img = models.ImageField(upload_to="course", max_length=255, verbose_name="封面图片", blank=True, null=True)
        course_type = models.SmallIntegerField(choices=course_type,default=0, verbose_name="付费类型")
        # 使用这个字段的原因
        video = models.FileField(upload_to="video", null=True,blank=True,default=None, verbose_name="封面视频")
        brief = RichTextUploadingField(max_length=2048, verbose_name="详情介绍", null=True, blank=True)
        level = models.SmallIntegerField(choices=level_choices, default=1, verbose_name="难度等级")
        pub_date = models.DateField(verbose_name="发布日期", auto_now_add=True)
        period = models.IntegerField(verbose_name="建议学习周期(day)", default=7)
        attachment_path = models.FileField(max_length=128, verbose_name="课件路径", blank=True, null=True)
        status = models.SmallIntegerField(choices=status_choices, default=0, verbose_name="课程状态")
        course_category = models.ForeignKey("CourseCategory", on_delete=models.CASCADE, null=True, blank=True,verbose_name="课程分类")
        students = models.IntegerField(verbose_name="学习人数",default = 0)
        lessons = models.IntegerField(verbose_name="总课时数量",default = 0)
        pub_lessons = models.IntegerField(verbose_name="课时更新数量",default = 0)
        price = models.DecimalField(max_digits=6,decimal_places=2, verbose_name="课程原价",default=0)
        teacher = models.ForeignKey("Teacher",on_delete=models.DO_NOTHING, null=True, blank=True,verbose_name="授课老师")
        class Meta:
            db_table = "ly_course"
            verbose_name = "专题课程"
            verbose_name_plural = "专题课程"
    
        def __str__(self):
            return "%s" % self.name
    
        def get_course_discount_type(self):
            now = datetime.now()
            try:
                course_prices = self.prices.get(start_time__lte=now, end_time__gte=now, is_delete=False, is_show=True)
                # 获取优惠活动类型
                return course_prices.discount.discount_type.name
            except:
                return ""
    
        def get_course_price(self):
            # 获取当前课程的真实价格
            # 获取当前课程的价格策略
    
            now = datetime.now()
            try:
                course_prices = self.prices.get( start_time__lte=now,end_time__gte=now, is_delete=False,is_show=True)
    
                # 价格优惠条件判断,原价大于优惠条件才参与活动
                if self.price < course_prices.discount.condition:
                    return self.price
    
                # 当优惠公式为多行文本,则表示满减
                if course_prices.discount.sale[0]=="满":
                    sale_list = course_prices.discount.sale.split("
    ")
                    sale_price_list = []
                    # 通过遍历提取所有策略项的优惠价格值
                    for sale_item in sale_list:
                        sale = int( sale_item[1: sale_item.index("-")] )
                        sele_price = int( sale_item[sale_item.index("-")+1:] )
                        if self.price >= sale:
                            sale_price_list.append( sele_price )
    
                    # 当前课程只能享受一个最大优惠
                    return self.price - max( sale_price_list )
    
                # 当优惠公式为-1,则表示真实价格为0
                if course_prices.discount.sale == "-1":
                    return 0
    
                # 当优惠公式为*开头,则表示折扣
                if course_prices.discount.sale[0] == "*":
                    sale = Decimal( course_prices.discount.sale[1:] )
                    return self.price * sale
    
                # 当优惠公式为负数,则表示减免
                if course_prices.discount.sale[0] == "-":
                    sale = Decimal( course_prices.discount.sale[1:] )
                    real_price = self.price - sale
                    return real_price if real_price > 0 else 0
    
            except:
                print("---没有优惠---")
    
            return self.price
    
        def lesson_list(self):
            """获取当前课程的前8个课时展示到列表中"""
    
            # 获取所有章节
            chapters_list = self.coursechapters.filter(is_delete=False,is_show=True)
            lesson_list = []
            if chapters_list:
                for chapter in chapters_list:
                    lessons = chapter.coursesections.filter(is_delete=False,is_show=True)[:4]
                    if lessons:
                        for lesson in lessons:
                            lesson_list.append({
                                "id":lesson.id,
                                "name":lesson.name,
                                "free_trail":lesson.free_trail
                            })
    
            return lesson_list[:4]
    
        def course_level(self):
            """把课程难度数值转换成文本"""
            return self.level_choices[self.level][1]
    
    class Teacher(BaseModel):
        """讲师、导师表"""
        。。。
    
    
    class CourseChapter(BaseModel):
        """课程章节"""
        。。。
    
    
    class CourseLesson(BaseModel):
        """课程课时"""
        。。。
    
    """价格相关的模型"""
    class PriceDiscountType(BaseModel):
        """课程优惠类型"""
        。。。
    
    class PriceDiscount(BaseModel):
        """课程优惠模型"""
        。。。
    
    class CoursePriceDiscount(BaseModel):
        """课程与优惠策略的关系表"""
        。。。
    
    

    修改序列化器,增加返回字段[优惠类型和优惠策略]

    from rest_framework import serializers
    from .models import CourseCategory,Course
    class CourseCategoryModelSerializer(serializers.ModelSerializer):
        class Meta:
            model = CourseCategory
            fields = ("id","name")
    
    from .models import Teacher
    class TeacherModelSerializer(serializers.ModelSerializer):
        class Meta:
            model = Teacher
            fields = ("id","name","title")
    
    class CourseModelSerializer(serializers.ModelSerializer):
       	"""课程列表页的序列化器"""
        # 默认情况,序列化器转换模型数据时,默认会把外键直接转成主键ID值
        # 所以我们需要重新设置在序列化器中针对外键的序列化
        # 这种操作就是一个序列器里面调用另一个序列化器了.叫"序列化器嵌套"
        teacher = TeacherModelSerializer()
        # coursechapters = CourseChapterModelSerializer(many=True)
        class Meta:
            model = Course
            fields = ("id","name","course_img","students","lessons","pub_lessons","price","teacher","lesson_list","get_course_price","get_course_discount_type")
    
    
    class TeacherDetailModelSerializer(serializers.ModelSerializer):
        。。。。
    
    
    class CourseDetailModelSerializer(serializers.ModelSerializer):
        """课程详情页的序列化器"""
        teacher = TeacherDetailModelSerializer()
        class Meta:
            model = Course
            # fields = ("id","name", "video", "course_img", "students","lessons","pub_lessons","price","teacher","course_level","brief")
            fields = ("id","name", "course_img", "students","lessons","pub_lessons","price","teacher","course_level","brief","get_course_price","get_course_discount_type")
    
    

    前端课程列表页展示真实课程价格

    判断是否有课程类型,如果有,则显示优惠价格。没有则显示课程原价。

    Course.vue

    <template>
      <div class="course">
        <Header/>
        <div class="main">
          <!-- 筛选功能 -->
          <div class="top">
            <ul class="condition condition1">
              <li class="cate-condition">课程分类:</li>
              <li class="item" :class="query_params.course_category==0?'current':''" @click="query_params.course_category=0">全部</li>
              <li :class="query_params.course_category==catetory.id?'current':''" @click="query_params.course_category=catetory.id" v-for="catetory in catetory_list" :data-key="catetory.id" class="item">{{catetory.name}}</li>
            </ul>
            <ul class="condition condition2">
              <li class="cate-condition">筛&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;选:</li>
              <li class="item" :class="(query_params.ordering=='-id' || query_params.ordering=='id')?'current':''" @click="select_ordering('id')">默认</li>
              <li class="item" :class="(query_params.ordering=='-students' || query_params.ordering=='students')?'current':''" @click="select_ordering('students')">人气</li>
              <li class="item" :class="query_params.ordering=='price'?'current price':(query_params.ordering=='-price'?'current price2':'')" @click="select_ordering('price')">价格</li>
              <li class="course-length">共21个课程</li>
            </ul>
          </div>
          <!-- 课程列表 --->
          <div class="list">
            <ul>
              <li class="course-item" v-for="course in course_list">
                <router-link :to="{path: '/detail',query:{id:course.id}}" class="course-link">
                  <div class="course-cover">
                    <img :src="course.course_img" alt="">
                  </div>
                  <div class="course-info">
                    <div class="course-title">
                      <h3>{{course.name}}</h3>
                      <span>{{course.students}}人已加入学习</span>
                    </div>
                    <p class="teacher">
                      <span class="info">{{course.teacher.name}} {{course.teacher.title}}</span>
                      <span class="lesson">共{{course.lessons}}课时/{{course.lessons==course.pub_lessons?'更新完成':('已更新'+course.pub_lessons+"课时")}}</span>
                    </p>
                    <ul class="lesson-list">
                      <li v-for="lesson,key in course.lesson_list">
                        <p class="lesson-title">0{{key+1}} | {{lesson.name}}</p>
                        <span v-if="lesson.free_trail" class="free">免费</span>
                      </li>
    
                    </ul>
                    <div class="buy-info">
                      <div v-if="course.get_course_discount_type">
                      <span class="discount">{{course.get_course_discount_type}}</span>
                      <span class="present-price">¥{{course.get_course_price}}元</span>
                      <span class="original-price">原价:{{course.price}}元</span>
                      </div>
                      <span v-else class="present-price">¥{{course.price}}元</span>
                      <button class="buy-now">立即购买</button>
                    </div>
                  </div>
                </router-link>
              </li>
            </ul>
          </div>
          <div class="pagination">
            <el-pagination
              @current-change="handleCurrentChange"
              :current-page="query_params.current_page"
              background
              layout="prev, pager, next"
              :page-size="course_page_size"
              :total="course_count">
            </el-pagination>
          </div>
        </div>
        <Footer/>
      </div>
    </template>
    
    

    前端课程详情页展示真实课程的价格

    Detail.vue

    <template>
        <div class="detail">
          <Header/>
          <div class="main">
            <div class="course-info">
              <div class="wrap-left">
                <video-player class="video-player vjs-custom-skin"
                   ref="videoPlayer"
                   :playsinline="true"
                   :options="playerOptions"
                   @play="onPlayerPlay($event)"
                   @pause="onPlayerPause($event)"
                >
                </video-player>
              </div>
              <div class="wrap-right">
                <h3 class="course-name">{{course.name}}</h3>
                <p class="data">{{course.students}}人在学&nbsp;&nbsp;&nbsp;&nbsp;课程总时长:{{course.lessons}}课时/{{course.lessons==course.pub_lessons?'更新完成':('已更新'+course.pub_lessons+"课程")}}&nbsp;&nbsp;&nbsp;&nbsp;难度:{{course.course_level}}</p>
                <div v-if="course.get_course_discount_type">
                <div class="sale-time">
                  <p class="sale-type">{{course.get_course_discount_type}}</p>
                  <p class="expire">距离结束:仅剩 01天 04小时 33分 <span class="second">08</span> 秒</p>
                </div>
                <p class="course-price">
                  <span>活动价</span>
                  <span class="discount">¥{{course.get_course_price}}</span>
                  <span class="original">¥{{course.price}}</span>
                </p>
                </div>
                <div v-else>
                <div class="sale-time">
                  <p class="sale-type">价格: ¥{{course.price}}</p>
                </div>
                </div>
                <div class="buy">
                  <div class="buy-btn">
                    <button class="buy-now">立即购买</button>
                    <button class="free">免费试学</button>
                  </div>
                  <div @click="cartAddHander" class="add-cart"><img src="@/assets/cart-yellow.svg" alt="">加入购物车</div>
                </div>
              </div>
            </div>
    		。。。。        
          </div>
          <Footer/>
        </div>
    </template>
    
    

    购物车结算

    实现课程详情页倒计时功能

    模型返回当前课程优惠的剩余时间戳

    courses/models.py中,Course模型新增计算剩余时间的方法,代码:

    from ckeditor_uploader.fields import RichTextUploadingField
    class Course(BaseModel):
        """
        专题课程
        """
        。。。
    
        def has_time(self):
            """计算活动的剩余时间"""
            now = datetime.now()
            try:
                course_prices = self.prices.get(start_time__lte=now, end_time__gte=now, is_delete=False, is_show=True)
                # 把 活动结束时间 - 当前时间 = 剩余时间
                return int( course_prices.end_time.timestamp() - now.timestamp() )
            except:
                print("---活动过期了----")
    
            return 0
    
    

    序列化器,新增返回字段

    class CourseDetailModelSerializer(serializers.ModelSerializer):
        """课程详情页的序列化器"""
        teacher = TeacherDetailModelSerializer()
        class Meta:
            model = Course
            # fields = ("id","name", "video", "course_img", "students","lessons","pub_lessons","price","teacher","course_level","brief")
            fields = ("id","name", "course_img", "students","lessons","pub_lessons","price","teacher","course_level","brief","get_course_price","get_course_discount_type","has_time")
    
    

    前端使用定时器setInterval完成倒计时功能

    <template>
        <div class="detail">
          <Header/>
          <div class="main">
            <div class="course-info">
              <div class="wrap-left">
                。。。。
                <div class="sale-time">
                  <p class="sale-type">{{course.get_course_discount_type}}</p>
                  <p class="expire">距离结束:仅剩 {{Math.floor(course.has_time/86400)}}天 {{Math.floor(course.has_time%86400/3600)}}小时 {{Math.floor(course.has_time%86400%3600/60)}}分 <span class="second">{{Math.floor(course.has_time%86400%3600%60)}}</span> 秒</p>
                </div>
                <p class="course-price">
                  <span>活动价</span>
                  <span class="discount">¥{{course.get_course_price}}</span>
                  <span class="original">¥{{course.price}}</span>
                </p>
                </div>
                <div v-else>
                <div class="sale-time">
                  <p class="sale-type">价格: ¥{{course.price}}</p>
                </div>
                </div>
                。。。。
    
    </template>
    <script>
    import Header from "./common/Header"
    import Footer from "./common/Footer"
    
    import {videoPlayer} from 'vue-video-player';
    
    export default {
        name: "Detail",
        。。。。
        created(){
          // 获取当前课程ID
          this.course_id = this.$route.query.id - 0;
          // 判断ID基本有效性
          let _this = this;
          if( isNaN(this.course_id) || this.course_id < 1 ){
            _this.$alert("无效的课程ID!","错误",{
              callback(){
                _this.$router.go(-1);
              }});
          }
          // 发送请求获取后端课程数据
          this.$axios.get(this.$settings.Host+`/courses/detail/${this.course_id}/`).then(response=>{
            this.course = response.data;
            // 修改视频中的封面图片
            this.playerOptions.poster = this.course.course_img;
            // 倒计时
            if(this.course.has_time > 1){
    
              let timer = setInterval(()=>{
                if( this.course.has_time > 1 ){
                  this.course.has_time-=1;
                }else{
                  clearInterval(timer);
                  location.reload();
                }
              },1000);
    
            }
    
          }).catch(error=>{
            console.log(error.response)
          });
        },
        。。。。
    }
    </script>
    
    

    根据课程有效期调整价格

    后端实现提供课程有效期的API

    模型代码:

    """课程有效期"""
    class CourseTime(BaseModel):
        """课程有效期表"""
        timer = models.IntegerField(verbose_name="购买周期",default=30,help_text="单位:天<br>建议按月书写,例如:1个月,则为30.")
        title = models.CharField(max_length=150, null=True, blank=True, verbose_name="购买周期的文本提示", default="1个月有效", help_text="要根据上面的购买周期,<br>声明对应的提示内容,<br>展示在购物车商品列表中")
        course = models.ForeignKey("Course", on_delete=models.CASCADE, related_name="coursetimes", verbose_name="课程")
        price = models.DecimalField(max_digits=6, decimal_places=2, verbose_name="课程原价", default=0)
    
        class Meta:
            db_table = "ly_course_time"
            verbose_name = "课程有效期表"
            verbose_name_plural = "课程有效期表"
    
        def __str__(self):
            return "课程:%s,周期:%s,价格:%s" % (self.course, self.timer, self.price)
    
    
    

    数据迁移

    python manage.py makemigrations
    python manage.py migrate
    
    

    把模型注册到xadmin中。

    from .models import CourseTime
    class CourseTimeModelAdmin(object):
        """课程与价格优惠关系模型管理类"""
        list_display = ["course","title","timer","price"]
    xadmin.site.register(CourseTime, CourseTimeModelAdmin)
    
    

    添加测试数据

    ![1558426132503](../03_luffy/day84 luffy(2))

    购物车视图中,返回购买课程的周期列表,cart/views.py,代码

    class CartAPIView(APIView):
        permission_classes = [IsAuthenticated]
        """购物车视图"""
        def get(self,request):
            """获取购物车商品课程列表"""
            # 获取当前用户ID
            # user_id = 1
            user_id = request.user.id
            # 通过用户ID获取购物车中的商品信息
            redis = get_redis_connection("cart")
            cart_goods_list = redis.hgetall("cart_%s" % user_id ) # 商品课程列表
            cart_goods_selects = redis.smembers("cart_selected_%s" % user_id)
            # redis里面的所有数据最终都是以bytes类型的字符串保存的
            # print( cart_goods_selects ) # 格式: {b'7', b'3', b'5'}
            # print( cart_goods_list ) # 格式: {b'7': b'-1', b'5': b'-1'}
            # 遍历购物车中的商品课程到数据库获取课程的价格, 标题, 图片
            data_list = []
            try:
                for course_id_bytes,expire_bytes in cart_goods_list.items():
                    course_id = int( course_id_bytes.decode() )
                    expire    = expire_bytes.decode()
                    course = Course.objects.get(pk=course_id)
    
                    # 获取购买的课程的周期价格列表
                    expires = course.coursetimes.all()
                    # 默认具有永久价格
                    expire_list = [{
                        "title": "永久有效",
                        "timer": -1,
                        "price": course.price
                    }]
                    for item in expires:
                        expire_list.append({
                            "title":item.title,
                            "timer":item.timer,
                            "price":item.price,
                        })
    
                    data_list.append({
                        "id": course_id,
                        "expire":expire,
                        "course_img": course.course_img.url,
                        "name": course.name,
                        "price": course.get_course_price(),
                        "is_select": course_id_bytes in cart_goods_selects,
                        "expire_list": expire_list,
                    })
            except:
                return Response(data_list,status=status.HTTP_500_INTERNAL_SERVER_ERROR)
            # print(data_list)
            # 返回查询结果
            return Response(data_list,status=status.HTTP_200_OK)
    
    

    前端展示购物车中每一个商品课程的购买周期,代码:

    <template>
        。。。。
                <el-table-column label="有效期" width="216">
                  <template slot-scope="scope">
                    <el-select @change="ChangeExpire(scope.row)" v-model="scope.row.expire" placeholder="请选择">
                      <el-option v-for="item in scope.row.expire_list" :key="item.timer" :label="item.title" :value="item.timer"></el-option>
                    </el-select>
                  </template>
                </el-table-column>
                。。。。
        </div>
    </template>
    
    <script>
    import Header from "./common/Header"
    import Footer from "./common/Footer"
    export default {
        name: "Cart",
        data(){
          return{
            // 注释掉原来的有效周期测试数据
            // expire:3,
            // expire_list:[]
            courseData:[], // 购物车中的商品信息
            selection:[],  // 购物车中被勾选的商品信息
            total_price:0.00,
          }
        },
        。。。。
        created(){
          // 判断是否登录
          this.token = sessionStorage.token || localStorage.token;
          if( !this.token ){
            this.$confirm("对不起,您尚未登录!请登录",'提示').then(() => {
              this.$router.push("/login");
            }).catch(()=>{
              this.$router.go(-1);
            });
          }else{
            // 获取购物车商品数据
            this.$axios.get(this.$settings.Host+"/carts/course/",{
              headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              }
            }).then(response=>{
    
              this.courseData = response.data;
              // 更新在vuex里面的数据
              this.$store.state.cart.count = response.data.length;
    
              // 调整因为ajax数据请求导致勾选状态人没有出现的原因,使用定时器进行延时调用
              setTimeout(()=>{
                let expire_data = [];
                this.courseData.forEach(course=>{
                  course.expire_list.forEach(row=>{
                    expire_data[row.timer] = row.title;
                  });
                });
    
                // row 就是字典数据[json]
                this.courseData.forEach(row => {
                  // 设置商品课程的选中状态
                  if(row.is_select){
                    this.$refs.multipleTable.toggleRowSelection(row);
                  }
                  // 调整有效期选项中数值变成文本内容
                  row.expire = expire_data[row.expire];
                });
              },0)
    
            }).catch(error=>{
              let status = error.response.status;
              if( status == 401 ){
                this.token = null;
                sessionStorage.removeItem("token");
                localStorage.removeItem("token");
                let _this = this;
                this.$alert("您尚未登录或登录超时!请重新登录","警告",{
                  callback(){
                    _this.$router.push("/login");
                  }
                });
              }
            })
    
          }
        },
        
        。。。
    }
    </script>
    
    
    

    当切换课程周期时,后端重新计算价格并返回

    模型中计算真实价格时,增加一个原价字段,通过原价字段,判断本次计算是计算周期还是计算永久有效。

    from ckeditor_uploader.fields import RichTextUploadingField
    class Course(BaseModel):
        """
        专题课程
        """
        。。。。
    
        def get_course_price(self,price=0):
            # 获取当前课程的真实价格
    
            self.price = price if price != 0 else self.price # 判断调用当前方法时,是否定义了价格
            
            。。。。
    
    

    视图中修改patch方法,在用户切换购买课程周期时,重新计算真实课程价格,代码:

    def patch(self,request):
            """更新购物城中的商品信息[切换课程有效期]"""
            # 获取当前登录的用户ID
            # user_id = 1
            user_id = request.user.id
    
            # 获取当前操作的课程ID
            course_id = request.data.get("course_id")
    
            # 获取新的有效期
            expire = request.data.get("expire")
    
            # 获取redis链接
            redis = get_redis_connection("cart")
    
            # 更新购物中商品课程的有效期
            redis.hset("cart_%s" % user_id,course_id, expire)
    
            # 根据新的课程有效期获取新的课程原价
            try:
                coursetime = CourseTime.objects.get(course=course_id, timer=expire)
                # 根据新的课程价格,计算真实课程价格
                price = coursetime.course.get_course_price(coursetime.price)
            except:
                # 这里给price设置一个默认值,当值-1,则前段不许要对价格进行调整
                course = Course.objects.get(pk=course_id)
                price = course.get_course_price()
    
    
            return Response({
                "price": price,
                "message": "修改购物车信息成功!"
            }, status=status.HTTP_200_OK)
    
    

    前端获取课程有效期列表

          // 更新课程的有效期
          ChangeExpire(course){
            // 获取课程ID和有效期
            let course_id = course.id;
            let expire    = course.expire;
    
            // 发送patch请求更新有效期
            this.$axios.patch(this.$settings.Host+"/carts/course/",{
              course_id,
              expire,  // 这里是简写,相当于 expire:expire,
            },{
              headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              },
            }).then(response=>{
              // 更新购买的商品课程的价格
              course.price = response.data.price;
              this.$message(response.data.message,"提示");
            });
          },
    
    

    完成上面的步骤以后,切换购买周期时,价格就发生了变化,但是购物车页面刷新时,发现价格还原成"永久有效"的价格。所以我们需要在后端的购物车商品列表api接口中针对价格的购买周期进行判断。

    carts/views.py的CartAPIView

        def get(self,request):
            """获取购物车商品课程列表"""
            # 获取当前用户ID
            # user_id = 1
            user_id = request.user.id
            # 通过用户ID获取购物车中的商品信息
            redis = get_redis_connection("cart")
            cart_goods_list = redis.hgetall("cart_%s" % user_id ) # 商品课程列表
            cart_goods_selects = redis.smembers("cart_selected_%s" % user_id)
            # redis里面的所有数据最终都是以bytes类型的字符串保存的
            # print( cart_goods_selects ) # 格式: {b'7', b'3', b'5'}
            # print( cart_goods_list ) # 格式: {b'7': b'-1', b'5': b'-1'}
            # 遍历购物车中的商品课程到数据库获取课程的价格, 标题, 图片
            data_list = []
            try:
                for course_id_bytes,expire_bytes in cart_goods_list.items():
                    course_id = int( course_id_bytes.decode() )
                    expire    = expire_bytes.decode()
                    course = Course.objects.get(pk=course_id)
    
                    # 获取购买的课程的周期价格列表
                    expires = course.coursetimes.all()
                    # 默认具有永久价格
                    expire_list = [{
                        "title": "永久有效",
                        "timer": -1,
                        "price": course.price
                    }]
                    for item in expires:
                        expire_list.append({
                            "title":item.title,
                            "timer":item.timer,
                            "price":item.price,
                        })
    
                    try:
                        # 根据课程有效期传入课程原价
                        coursetime = CourseTime.objects.get(course=course_id, timer=expire)
                        # 根据新的课程价格,计算真实课程价格
                        price= coursetime.price
                    except:
                        price = 0
    
                    data_list.append({
                        "id": course_id,
                        "expire":expire,
                        "course_img": course.course_img.url,
                        "name": course.name,
                        "price": course.get_course_price(price),
                        "is_select": course_id_bytes in cart_goods_selects,
                        "expire_list": expire_list,
                    })
            except:
                return Response(data_list,status=status.HTTP_500_INTERNAL_SERVER_ERROR)
            # print(data_list)
            # 返回查询结果
            return Response(data_list,status=status.HTTP_200_OK)
    
    
    

    最后,修复在用户切换购买周期时,前端需要重新计算购物车中所有商品的总价格。

    // 更新课程的有效期
          ChangeExpire(course){
            // 获取课程ID和有效期
            let course_id = course.id;
            let expire    = course.expire;
    
            // 发送patch请求更新有效期
            this.$axios.patch(this.$settings.Host+"/carts/course/",{
              course_id,
              expire,  // 这里是简写,相当于 expire:expire,
            },{
              headers:{
                // 注意下方的空格!!!
                "Authorization":"jwt " + this.token
              },
            }).then(response=>{
              // 更新购买的商品课程的价格
              course.price = response.data.price;
              // 重新计算购物车中的商品总价
              this.getTotalPrice();
              this.$message(response.data.message,"提示");
            });
          },
    
    
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  • 原文地址:https://www.cnblogs.com/pankypan/p/11300283.html
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