python 自定义分页

后台：

分页工具类：

class PageHelper:
    def __init__(self):
        pass


    def getStart(self,current_page,pre_page=10):
        return (current_page - 1) * pre_page
    def getEnd(self,current_page,pre_page=10):
        return  current_page*pre_page

    # pre_page:每页显示的记录数
    def page_str(self,toal_count,current_page,base_url,pre_page=10):
        # 每页显示10条数据
        # divmod 方法返回两个值一个是商，一个是余数
        v, a = divmod(toal_count, pre_page)
        if a != 0:
            v += 1
        pager_list = []
        if current_page > 1:
            pager_list.append('<a href = "%s?p=%s" >上一页</a>' % (base_url,current_page - 1))

        # 总页数<=11
        #     page_start=1
        #     page_end= 总页数
        #
        # 总页数 > 11
        #     当前页<6
        #         page_start=1
        #         page_end=11
        #     else
        #         page_start = 当前页 -5
        #          page_end = 当前页 + 6
        #          if page_end> 总页数
        #               page_end = 总页数
        #
        #
        if v <= 11:
            page_start = 1
            page_end = v + 1
        else:
            if current_page < 6:
                page_start = 1
                page_end = 12
            else:
                page_start = current_page - 5
                page_end = current_page + 6
                if page_end > v:
                    page_start = v - 10
                    page_end = v + 1

        for i in range(page_start, page_end):
            # 为当前页设置class，让用户可以知道当前是第几页
            if i == current_page:
                pager_list.append('<a class="active" href = "%s?p=%s" >%s</a>' % (base_url,i, i))
            else:
                pager_list.append('<a href = "%s?p=%s" >%s</a>' % (base_url,i, i))


        # pager = '''
        #     <a href="classes.html?p=1">1</a>
        #     <a href="classes.html?p=2">2</a>
        #     <a href="classes.html?p=3">3</a>
        # '''

        if current_page < v:
            pager_list.append('<a href = "%s?p=%s" >下一页</a>' % (base_url,current_page + 1))

        pager = "".join(pager_list)
        return pager

调用分页类：

def handle_classes(req):
    if req.method == "GET":
        current_user = req.session.get('username')

        # 获取当前页，p的值默认是1
        current_page = req.GET.get('p',1)
        current_page = int(current_page)


        pre_page = 5

        #获取数据库中记录总数
        toal_count = models.Classes.objects.all().count()
        obj = PageHelper()
        start =obj.getStart(current_page,pre_page)
        end = obj.getEnd(current_page,pre_page)

        #获取班级列表
        cls_list = models.Classes.objects.all()[start:end]

        pager = obj.page_str(toal_count,current_page,'classes.html',pre_page)

        #返回到前端
        #Django有防止xss攻击的机制，mark_safe() 表示取消xss 攻击，让pager 中的内容显示成正常的html标签
        #第二种方式是在前端加{{str_pager|safe}}
        return render(req,'classes.html',
                  {'username':current_user,
                   'cls_list':cls_list,
                   'str_pager':mark_safe(pager)
                   })

前端

html

<div class="pageination">
  {{str_pager}}
</div>

css

       .pageination a{
            display: inline-block;
            padding: 5px;
        }
         .pageination a.active{
             background-color: gold;
             color: red;
         }