web框架开发-分页器(Paginator)

Django有自带的分页器,可以将数据分在不同的页面中,并提供一些属性和方法实现对分页数据的操作。分页功能的类位于django/core/paginator.py中。

常用方法

# 分页器
    # paginator分页器对象(obj,每页条数)
    paginator = Paginator(book_list, 3)

    ################常用方法#################
    print("count:", paginator.count)  # 数据总数
    print("num_pages", paginator.num_pages)  # 总页数
    print("page_range", paginator.page_range)  # 页码的列表

    #################提取某一页具体数据的两种方式#################
    # 方式1
    page1 = paginator.page(1)  # 第1页的page对象
    for i in page1:  # 遍历第1页的所有数据对象
        print(i)
    # 方式2
    print(page1.object_list)  # 第1页的所有数据



实例代码

index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
<h3>图书列表</h3>
    <ul>
        {% for book_obj in current_page %}
            <li>{{ book_obj.title }}:{{ book_obj.price }}</li>
        {% endfor %}
        
    </ul>

    <nav aria-label="Page navigation">
        <ul class="pagination">
{#              上一页#}
        {% if current_page.has_previous %}
            <li>
                <a href="?page={{ current_page.previous_page_number }}" aria-label="Previous">
                    <span aria-hidden="true">上一页</span>
                </a>
            </li>
        {% else %}
{#            如果没有上一页了,就把标签禁止,且没有连接#}
            <li class="disabled">
                <a href="" aria-label="Previous">
                    <span aria-hidden="true">上一页</span>
                </a>
            </li>
        {% endif %}

{#              中间的页码#}
            {% for page in page_range %}
{#                如果循环的页码等于当前的页码,就添加active#}
                {% if current_page_num == page%}
                    <li class="active"><a href="?page={{ page }}">{{ page }}</a></li>
                {% else %}
                    <li><a href="?page={{ page }}">{{ page }}</a></li>
                {% endif %}
            {% endfor %}

{#              下一页#}
        {% if current_page.has_next %}
            <li>
                <a href="?page={{ current_page.next_page_number }}" aria-label="Next">
                    <span aria-hidden="true">下一页</span>
                </a>
            </li>
        {% else %}
{#            如果没有下一页了,就把标签禁止,且没有连接#}
            <li class="disabled">
                <a href="" aria-label="Next">
                    <span aria-hidden="true">下一页</span>
                </a>
            </li>
        {% endif %}

  </ul>
</nav>
</body>
</html>


views.py

from django.shortcuts import render
from app01.models import *
from django.core.paginator import Paginator


# Create your views here.


def index(request):
    """
    批量导入数据到数据库
    book_list=[]
    for i in range(100):
        book=Book(title="book%s"%i,price=i*i)
        book_list.append(book)
    Book.objects.bulk_create(book_list)
    :param request:
    :return:
    """
    # 拿到所有的数据书籍
    book_obj_list = Book.objects.all()
    # 生成分页器对象
    paginator = Paginator(book_obj_list, 3)
    # 获取浏览器端请求的页码,需要设置默认值
    current_page_num = int(request.GET.get('page', 1))
    # 当前页的所有书对象
    current_page = paginator.page(current_page_num)
    # 页码列表,可迭代
    # 分页过多,需要用条件判断显示的页码
    if paginator.num_pages > 11:  # 11就是显示的固定个数
        if current_page_num - 5 < 1:  # 接近最小页码时,固定页码,否则会出现负数
            page_range = range(1, 12)
        elif current_page_num + 5 > paginator.num_pages: # 接近最大页码时,根据最大页码限制页码数,否则会出现不存在的页码
            page_range = range(paginator.num_pages - 10, paginator.num_pages + 1)
        else:
            page_range = range(current_page_num - 5, current_page_num + 6)  # 其他情况,显示当前的挨着的几个
    else:
        page_range = paginator.page_range  # 页码总数不足时,显示全部,即不会超宽

    return render(request, 'index.html', locals())

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转载自www.cnblogs.com/yxiaodao/p/9544959.html