• 分页器


    Django自带的分页器组件不太好用, 这里选择自定义一个分页器组件.

    自定义分页器

    class Pagination(object):
        def __init__(self, current_page, all_count, per_page_num=5, 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.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
    
        @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):
            # 根据当前页面的page数确认下面的渲染标签的起始和终止
            count_half = self.pager_count // 2
    
            pager_start = self.current_page - count_half if self.current_page > count_half else 1
            pager_end = self.current_page + count_half if self.current_page < self.all_pager - count_half else self.all_pager
    
            if pager_start == 1:
                pager_end = self.pager_count if self.pager_count > self.all_pager else self.pager_count
            if pager_end == self.all_pager:
                pager_start = self.all_pager - self.pager_count if self.all_pager > self.pager_count else 1
    
            page_html_list = 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 + 1):
                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)
    

    使用分页器的例子

    views.py

    def books(request):
        # 这里就不查询数据库了, 直接生成一个列表数据
        book_list = [
            {'id': i, 'name': f'第{i}本书'} for i in range(1, 101)
        ]
        page = request.GET.get('page')
        # 导入分页器类.
        pagination = Pagination(page, len(book_list))
    
        book_set = book_list[pagination.start:pagination.end]
        return render(request, 'books.html', {'book_set': book_set, 'pagination': pagination})
    

    books.html

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <link href="https://cdn.bootcss.com/twitter-bootstrap/3.4.1/css/bootstrap.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.min.js"></script>
        <title>Title</title>
    </head>
    <body>
    <div class="container">
        <div class="row">
            <div class="col-md-offset-2 col-md-8">
                <h2>书籍展示</h2>
                <hr>
                <table class="table-hover table table-striped table-bordered">
                    <thead>
                    <tr>
                        <th>id</th>
                        <th>name</th>
                    </tr>
                    </thead>
                    <tbody>
                    {% for book in book_set %}
                        <tr>
                            <td>{{ book.id }}</td>
                            <td>{{ book.name }}</td>
                        </tr>
                    {% endfor %}
                    </tbody>
                </table>
                {#动态生成分页器#}
                <div class="text-center">{{ pagination.page_html|safe }}</div>
            </div>
        </div>
    </div>
    </body>
    </html>
    

    最后的效果

  • 相关阅读:
    要想成为前端大神,那些你不得不知晓的web前端命名规范。
    正确开启Mockjs的三种姿势:入门参考(一)
    1024码农节-向自己致敬!
    ES6 常用总结(前端开发js技术进阶提升总结)
    JS快速构建数组方法
    React绑定事件动态化的实现方法
    JQ遇到$(‘.xxx’).attr(‘display’)一直返回undefined
    你所要掌握的最简单基础的React渲染优化
    MyBatis Generator
    Spring boot集成redis初体验
  • 原文地址:https://www.cnblogs.com/yscl/p/11611216.html
Copyright © 2020-2023  润新知