python自定义分页器

自定义分页器

自定义分页器类

class Pagination(object):
    def __init__(self, current_page, all_count, per_page_num=10, pager_count=7):
        """
        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 < 7个：
        if self.all_pager <= self.pager_count:
            pager_start = 1
            pager_end = self.all_pager + 1
        # 总页码  > 7
        else:
            # 当前页如果<=页面上最多显示7/2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3
            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'>
                ''')
        if self.current_page == 1:
            first_page = '<li class="disabled"><a href="javascript:;">首页</a></li>'
        else:
            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="javascript:;">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="javascript:;">%s</a></li>' % (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)

        if self.current_page == self.all_pager:
            last_page = '<li class="disabled"><a href="javascript:;">尾页</a></li>'
        else:
            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)

用法：

后端

from utils.Page import Pagination

def user_list(request):

    user_ls = models.User.objects.all()   # 获取全部数据

    current_page = request.GET.get("page", 1)   # 获取当前页码数
    all_count = user_ls.count()   # 获取数据总条数
    page_obj = Pagination(current_page = current_page, all_count= all_count)   # 创建分页器对象，将当前页数，总条数传进去
    page_query = user_ls[page_obj.start: page_obj.end]   # 对数据进行切片取出

    return render(request, 'user_list.html', locals())   # 将数据返回页面

前端

# 循环 将数据显示到页面上
{% for user_obj in page_query %}
	<p>{{ user_obj.name }}</p>
{% endfor %}
# 获取分页器对象执行分页器方法
{{ page_obj.page_html|safe }}

效果图