分页

分页

第一步在视图中写(在get方法中得到:page，per_page，total_num)

def shop_info_view(request):
    section = '店铺信息'
    if request.method == 'GET':
        shopinfo = ShopInfo.objects.filter(logic_delete=False)
        total_num = shopinfo.count()

        if request.GET.get('page'):
            page = int(request.GET.get('page'))
        else:
            page = 1
        if request.GET.get('per_page'):
            per_page = int(request.GET.get('per_page'))
        else:
            per_page = 10

        shopinfo = shopinfo[(page-1)*per_page:page*per_page]

　　　　　context = {
    　　　　'section': section,
    　　　　'shopinfo': shopinfo,
    　　　　'page': page,
    　　　　'per_page': per_page,
    　　　　'total_num': total_num
　　　　　　}
　　　　return render(request, 'shopincomes/shopinfo.html', context=context)
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第二步创建一个过滤器标签(文件名：shop_info_filter.py)

from django.template import Library
import math
register = Library()


@register.inclusion_tag('shopincomes/paginate.html')
def paginate(page, per_page, total_num):
    # 要显示的页码表
    # 总页码
    num = 3    # 总共显示多少页码，一般都是奇数
    page_list = [ ]    #要显示的页码
    total_page = math.ceil(total_num/per_page)   #向上整除，只要有小数就进一位

    # 先算当前页左边的页码，看看需不需从第一页显示起
    if page - (num-1)//2 <= 0:
        for i in range(page):
            page_list.append(i+1)  #i+1,表示页码是从1开始的
    else:
        for i in range(page-(num-1)//2, page+1):
            page_list.append(i)

    # 再算右边，看看需不需要显示到最后一页
    if page + num >= total_page:
        for i in range(page+1, total_page+1):
            page_list.append(i)
    else:
        for i in range(page+1, page+num+1):
            page_list.append(i)

    if page > 1:
        has_pre = True
    else:
        has_pre = False
    if page < total_page:
        has_nex = True
    else:
        has_nex = False

    return {'page': page,
            'per_page': per_page,
            'total_num': total_num,
            'page_list': page_list,
            'has_pre': has_pre,
            'has_nex': has_nex,
            }
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第三步新建一个html文件（文件名：paginate.html）

  <ul class="pagination">

    <li {% if not has_pre %}class="disabled"{% endif %}>
      <a href="{% if has_pre %}{% url 'shopincomes:shop_info_view' %}?page={{ page|add:-1 }}&per_page={{ per_page }}{% endif %}" aria-label="Previous">
        <span aria-hidden="true">上一页</span>
      </a>
    </li>

{% for item in page_list %}
    <li {% if page == item %}class="active"{% endif %}><a href="{% url 'shopincomes:shop_info_view' %}?page={{ item }}&per_page={{ per_page }}">{{ item }}</a></li>
{% endfor %}

    <li {% if not has_nex %}class="disabled"{% endif %}>
      <a href="{% if has_nex %}{% url 'shopincomes:shop_info_view' %}?page={{ page|add:1 }}&per_page={{ per_page }}{% endif %}" aria-label="Next">

        <span aria-hidden="true">下一页</span>
      </a>
    </li>
  </ul>
    <div class="btn-group" style="margin-bottom: 65px">
  <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" >
   {{ per_page }}条/页 <span class="caret"></span>
  </button>
  <ul class="dropdown-menu">
    <li><a href="{% url 'shopincomes:shop_info_view' %}?page={{ page }}&per_page=10">10条/页</a></li>
    <li><a href="{% url 'shopincomes:shop_info_view' %}?page={{ page }}&per_page=25">25条/页</a></li>
    <li><a href="{% url 'shopincomes:shop_info_view' %}?page={{ page }}&per_page=50">50条/页</a></li>
    <li><a href="{% url 'shopincomes:shop_info_view' %}?page={{ page }}&per_page=100">100条/页</a></li>
    <li role="separator" class="divider"></li>
  </ul>
</div>
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第四步在页面中渲染

{% load shop_info_filter %}    #导入过滤器文件

<nav aria-label="Page navigation">
<li>总共有：{{ total_num }}条数据</li>
    {% paginate page per_page total_num %}
</nav>