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

原文地址:https://www.cnblogs.com/yscl/p/11611216.html