zoukankan      html  css  js  c++  java
  • 分页器

    class Pagination(object):
        def __init__(self, current_page, all_count, per_page_num=10, pager_count=11):
            """
            封装分页相关数据
            :param current_page: 当前页
            :param all_count:    数据库中的数据总条数
            :param per_page_num: 每页显示的数据条数
            :param pager_count:  最多显示的页码个数
    
            用法:
            queryset = model.objects.all()
            page_obj = Pagination(current_page,all_count)
            page_data = queryset[page_obj.start:page_obj.end]
            获取数据用page_data而不再使用原始的queryset
            获取前端分页样式用page_obj.page_html
            """
            try:
                current_page = int(current_page)
            except Exception as e:
                current_page = 1
    
            if current_page < 1:
                current_page = 1
    
            self.current_page = current_page
    
            self.all_count = all_count
            self.per_page_num = per_page_num
    
            # 总页码
            all_pager, tmp = divmod(all_count, per_page_num)
            if tmp:
                all_pager += 1
            self.all_pager = all_pager
    
            self.pager_count = pager_count
            self.pager_count_half = int((pager_count - 1) / 2)
    
        @property
        def start(self):
            return (self.current_page - 1) * self.per_page_num
    
        @property
        def end(self):
            return self.current_page * self.per_page_num
    
        def page_html(self):
            # 如果总页码 < 11个:
            if self.all_pager <= self.pager_count:
                pager_start = 1
                pager_end = self.all_pager + 1
            # 总页码  > 11
            else:
                # 当前页如果<=页面上最多显示11/2个页码
                if self.current_page <= self.pager_count_half:
                    pager_start = 1
                    pager_end = self.pager_count + 1
    
                # 当前页大于5
                else:
                    # 页码翻到最后
                    if (self.current_page + self.pager_count_half) > self.all_pager:
                        pager_end = self.all_pager + 1
                        pager_start = self.all_pager - self.pager_count + 1
                    else:
                        pager_start = self.current_page - self.pager_count_half
                        pager_end = self.current_page + self.pager_count_half + 1
    
            page_html_list = []
            # 添加前面的nav和ul标签
            page_html_list.append('''
                        <nav aria-label='Page navigation>'
                        <ul class='pagination'>
                    ''')
            first_page = '<li><a href="?page=%s">首页</a></li>' % (1)
            page_html_list.append(first_page)
    
            if self.current_page <= 1:
                prev_page = '<li class="disabled"><a href="#">上一页</a></li>'
            else:
                prev_page = '<li><a href="?page=%s">上一页</a></li>' % (self.current_page - 1,)
    
            page_html_list.append(prev_page)
    
            for i in range(pager_start, pager_end):
                if i == self.current_page:
                    temp = '<li class="active"><a href="?page=%s">%s</a></li>' % (i, i,)
                else:
                    temp = '<li><a href="?page=%s">%s</a></li>' % (i, i,)
                page_html_list.append(temp)
    
            if self.current_page >= self.all_pager:
                next_page = '<li class="disabled"><a href="#">下一页</a></li>'
            else:
                next_page = '<li><a href="?page=%s">下一页</a></li>' % (self.current_page + 1,)
            page_html_list.append(next_page)
    
            last_page = '<li><a href="?page=%s">尾页</a></li>' % (self.all_pager,)
            page_html_list.append(last_page)
            # 尾部添加标签
            page_html_list.append('''
                                               </nav>
                                               </ul>
                                           ''')
            return ''.join(page_html_list)
    View Code

    视图层调用方法

    from django.contrib.auth.decorators import login_required
    from app01.utils.my_page import Pagination
    @login_required
    def backend(request):
        article_list = models.Article.objects.filter(blog=request.user.blog)
        # 用户想访问的当前页面
        current_page = request.GET.get('page',1)
        # 用户总条数
        all_count = article_list.count()
        page_obj = Pagination(current_page=current_page,all_count=all_count)
        # 对数据进行切分
        page_queryset = article_list[page_obj.start:page_obj.end]
        return render(request,'backend/backend.html',locals())

    前端调用方法

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <link href="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/css/bootstrap.min.css" rel="stylesheet">
        <script src="https://cdn.bootcss.com/sweetalert/2.1.2/sweetalert.min.js"></script>
        <link href="//netdna.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet">
        <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
        <script src="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/js/bootstrap.js"></script>
    </head>
    <body>
    <nav class="navbar navbar-inverse">
        <div class="container-fluid">
            <!-- Brand and toggle get grouped for better mobile display -->
            <div class="navbar-header">
                <button type="button" class="navbar-toggle collapsed" data-toggle="collapse"
                        data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
                    <span class="sr-only">Toggle navigation</span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                </button>
                <a class="navbar-brand" href="#">后台管理</a>
            </div>
            <!-- Collect the nav links, forms, and other content for toggling -->
            <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
                <ul class="nav navbar-nav navbar-right">
                    {% if request.user.is_authenticated %}
                        <li><a href="">{{ request.user.username }}</a></li>
                        <li class="dropdown">
                            <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true"
                               aria-expanded="false">更多操作 <span class="caret"></span></a>
                            <ul class="dropdown-menu">
                                <li><a href="{% url 'edit_password' %}">修改密码</a></li>
                                <li><a href="#">修改头像</a></li>
                                <li role="separator" class="divider"></li>
                                <li><a href="{% url 'logout' %}">注销</a></li>
                            </ul>
                        </li>
    
                    {% endif %}
    
                </ul>
            </div><!-- /.navbar-collapse -->
        </div><!-- /.container-fluid -->
    </nav>
    <div class="container-fluid">
        <div class="row">
            <div class="col-md-3">
                <div class="panel-group" id="accordion" role="tablist" aria-multiselectable="true">
                    <div class="panel panel-default">
                        <div class="panel-heading" role="tab" id="headingOne">
                            <h4 class="panel-title">
                                <a role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseOne"
                                   aria-expanded="true" aria-controls="collapseOne">
                                    操作
                                </a>
                            </h4>
                        </div>
                        <div id="collapseOne" class="panel-collapse collapse in" role="tabpanel"
                             aria-labelledby="headingOne">
                            <div class="panel-body">
                                <a href="//">添加文章</a>
                            </div>
                        </div>
                        <div id="collapseOne" class="panel-collapse collapse in" role="tabpanel"
                             aria-labelledby="headingOne">
                            <div class="panel-body">
                                <a href="">添加随笔</a>
                            </div>
                        </div>
                        <div id="collapseOne" class="panel-collapse collapse in" role="tabpanel"
                             aria-labelledby="headingOne">
                            <div class="panel-body">
                                <a href="">垃圾箱</a>
                            </div>
                        </div>
                    </div>
                </div>
    
            </div>
             <div class="col-md-9">
                    <div>
                        <!-- Nav tabs -->
                        <ul class="nav nav-tabs" role="tablist">
                            <li role="presentation" class="active"><a href="#home" aria-controls="home" role="tab"
                                                                      data-toggle="tab">文章</a></li>
                            <li role="presentation"><a href="#profile" aria-controls="profile" role="tab" data-toggle="tab">随笔</a>
                            </li>
                            <li role="presentation"><a href="#messages" aria-controls="messages" role="tab"
                                                       data-toggle="tab">设置</a></li>
                            <li role="presentation"><a href="#settings" aria-controls="settings" role="tab"
                                                       data-toggle="tab">更多</a></li>
                        </ul>
    
                        <!-- Tab panes -->
                        <div class="tab-content">
                            <div role="tabpanel" class="tab-pane active" id="home">
    
                                  <table class="table table-hover table-striped">
                                    <thead>
                                        <tr>
                                            <th>标题</th>
                                            <th>发布时间</th>
                                            <th>评论数</th>
                                            <th>点赞数</th>
                                            <th>操作</th>
                                        </tr>
                                    </thead>
                                    <tbody>
                                    {% for article in page_queryset %}
                                        <tr>
                                            <td><a href="/{{ article.blog.userinfo.username }}/article/{{ article.pk }}">{{ article.title }}</a></td>
                                            <td>{{ article.create_time|date:'Y年m月d日' }}</td>
                                            <td>{{ article.common_num }}</td>
                                            <td>{{ article.up_num }}</td>
                                            <td></td>
                                        </tr>
                                    {% endfor %}
                                    </tbody>
                                </table>
                    {{ page_obj.page_html|safe }}
                                
                              
                            </div>
                            <div role="tabpanel" class="tab-pane" id="profile">...</div>
                            <div role="tabpanel" class="tab-pane" id="messages">...</div>
                            <div role="tabpanel" class="tab-pane" id="settings">...</div>
                        </div>
    
                    </div>
                </div>
        </div>
    
    </div>
    </body>
    </html>
    View Code

    1 循环打印对象替换为 page_queryset

    2 在分页位置插入  {{page_obj.page_html | safe }} 引用分页器

  • 相关阅读:
    ThingJS,轻松切换3D场景!
    ThingJS,以可视化的方式解决管线难题
    可视化能成为物联网“最后一公里”么?
    ThingJS 新手教程之初识在线开发(一)
    threejs和ThingJS的区别,ThingJS收费么?
    带你了解为什么许多公司都会选择使用ThingJS制作Demo进行投标!
    物联网可视化平台有哪些?ThingJS怎么样?
    ThingJS园区搭建工具模模搭介绍
    ThingJS,物联网可视化方面的专家平台!
    ajax的post的方法,不报错,就是不输出信息
  • 原文地址:https://www.cnblogs.com/guanchao/p/11082933.html
Copyright © 2011-2022 走看看