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  • Django自定义分页器

    自定义分页器,用于django在后端查询出来的数据,展示到前端页面,以分页的形式展示出来。

    1、将封装好的代码,写入py文件中,例如:mypagination.py

    # mypagination.py
     
    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
            """
            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)
    

    2、导入后端,将查询的数据交给自定义分页器处理,然后再返回给前端

    # 示例一
    from app01.utils.mypagination import Pagination
     
     
    def home(request):
        # 将网站所有的文章全部查询出来展示到前端
        article_list = models.Article.objects.all()
        page_obj = Pagination(current_page=request.GET.get('page', 1), all_count=article_list.count())
        page_queryset = article_list[page_obj.start:page_obj.end]
        return render(request, 'home.html', locals())
     
     
    # 示例二
    from mypagination import Pagination
     
    def get_book(request):
       book_list = models.Book.objects.all()
       current_page = request.GET.get("page",1)
       all_count = book_list.count()
       page_obj = Pagination(current_page=current_page,all_count=all_count,per_page_num=10)
       page_queryset = book_list[page_obj.start:page_obj.end]
       return render(request,'booklist.html',locals())
    

    3、前端渲染

    <!--示例一-->
            <div class="col-md-8">
                <ul class="media-list">
                    {% for article_obj in page_queryset %}
                        <li class="media">
                        <h4 class="media-heading"><a href="#">{{ article_obj.title }}</a></h4>
                        <div class="media-left">
                            <a href="#">
                                <img class="media-object" src="/static/image/default.jpg" alt="..." width="60">
                            </a>
                        </div>
                        <div class="media-body">
                            {{ article_obj.desc }}
                        </div>
                            <br>
                        <div>
                            <span><a href="#">{{ article_obj.blog.userinfo.username }}</a>&nbsp;</span>
                            <span>发布于&nbsp;</span>
                            <span>{{ article_obj.create_time|date:'Y-m-d' }}&nbsp;&nbsp;</span>
                            <span>评论({{ article_obj.comment_num }})&nbsp;&nbsp;</span>
                            <span>点赞({{ article_obj.up_num }})</span>
                        </div>
                    </li>
                        <hr>
                    {% endfor %}
                </ul>
                <!--分页器-->
            <div class="text-center">{{ page_obj.page_html|safe }}</div>
            </div>
     
     
    <!--示例二-->
    <div class="container">
        <div class="row">
            <div class="col-md-8 col-md-offset-2">
                <!--使用for循环,将后端传过来的多条数据渲染出来-->
                {% for book in page_queryset %}
                <p>{{ book.title }}</p>
                {% endfor %}
                <!--分页器-->
                {{ page_obj.page_html|safe }}
            </div>
        </div>
    </div>
    
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  • 原文地址:https://www.cnblogs.com/cnhyk/p/12274386.html
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