Django组件之分页器

一、批量插入

def index(request):
  # 一次一次地插入:
  for i in range(100):
  models.Book.objects.create(name='图书%s'%i,price=10+i)
  # 批量插入
  # 先造成100本书,放到列表中
  list1=[]
  for i in range(100):
  list1.append(models.Book(name='图书%s'%i,price=10+i))
  # 批量插入,两个参数,第一个是对象列表,第二个是一次插入的数据量,不填,默认一次全插入
  models.Book.objects.bulk_create(list1)

 二、分页器

# 导入分页器类
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger

# 实例化产生一个对象,两个参数:object_list(对象列表),per_page(每页显示条数)
paginator = Paginator(object_list,per_page)

# 对象内的属性
paginator.count  # 数据总条数

paginator.num_pages  # 总页数

paginator.page_range  # 页码数的列表

current_page=paginator.page(num)  # 当前页取到第num页,返回一个Page对象

current_page.object_list  # 当前页码内所有的数据

# 对象内的方法
current_page.has_next()  # 是否有下一页

current_page.has_previous()  # 是否有上一页

current_page.next_page_number()  # 下一页页码数

current_page.previous_page_number()  # 上一页的页码数

模板层

  1. for循环总页列表
  2. 点某一页,跳到指定页码,<li><a href="/index/?page={{ foo }}">{{ foo }}</a></li>
  3. 上一页,下一页的处理:需要有判断,判断是否有上一页,下一页
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div class="row">
    <div class="col-md-6 col-md-offset-3">

        <table class="table table-striped">
            <thead>
            <tr>
                <th>书名</th>
                <th>价格</th>
            </tr>
            </thead>
            <tbody>
            {% for book in current_page %}
                <tr>
                    <td>{{ book.name }}</td>
                    <td>{{ book.price }}</td>
                </tr>
            {% endfor %}

            </tbody>
        </table>
        <nav aria-label="Page navigation">
            <ul class="pagination">
                {% if current_page.has_previous %}
                    <li>
                        {#点击跳转上一页的两种写法#}
                        {#<a href="/index/?page={{ current_page_num|add:-1 }}" aria-label="Previous">#}
                        <a href="/index/?page={{ current_page.previous_page_number }}" aria-label="Previous">
                            <span aria-hidden="true">上一页</span>
                        </a>
                    </li>
                {% else %}
                    {#排除第一页没有上一页的情况,不可点击#}
                    <li class="disabled">
                        <a href="" aria-label="Previous">
                            <span aria-hidden="true">上一页</span>
                        </a>
                    </li>
                {% endif %}

                {% for foo in page_range %}
                    {% if current_page_num == foo %}
                        {# 当前页码等于循环到的页码数,变色#}
                        <li class="active"><a href="/index/?page={{ foo }}">{{ foo }}</a></li>
                    {% else %}
                        <li><a href="?page={{ foo }}">{{ foo }}</a></li>
                    {% endif %}

                {% endfor %}



                {% if current_page.has_next %}
                    <li>
                        {#点击跳转下一页的两种写法#}
                        {#<a href="/index/?page={{ current_page_num|add:1 }}" aria-label="Next">#}
                        <a href="/index/?page={{ current_page.next_page_number }}" aria-label="Next">
                            <span aria-hidden="true">下一页</span>
                        </a>
                    </li>
                {% else %}
                    {#排除最后一页没有下一页的情况,不可点击#}
                    <li class="disabled">
                        <a href="" aria-label="Next">
                            <span aria-hidden="true">下一页</span>
                        </a>
                    </li>
                {% endif %}
            </ul>
        </nav>
    </div>

</div>
</body>
</html>

视图层

def index(request):
    book_list = models.Book.objects.all()
    paginator = Paginator(book_list, 3)
    # 如果页码数多,让它显示前5,后5,中间是当前在的页码
    try:
        current_page_num = int(request.GET.get('page'))
        current_page = paginator.page(current_page_num)
        print(current_page.object_list)
        # 总页码数,大于11的时候
        if paginator.num_pages >11:
            # 当前页码数-5大于1的时候,page_range应该是?
            if current_page_num-5<1:
                page_range=range(1,12)
            elif current_page_num+5>paginator.num_pages:
                #     当前页码数+5大于总页码数,总页码数往前推11个
                page_range=range(paginator.num_pages-10,paginator.num_pages+1)
            else:
                page_range = range(current_page_num - 5, current_page_num + 6)
        else:
            #小于11,有多少页,就显示多少页
            page_range=paginator.page_range
    # 捕获异常后,跳到第一页
    except Exception as e:
        current_page_num = 1
        current_page = paginator.page(current_page_num)

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

posted on 2019-07-25 20:32  慕子尔  阅读(94)  评论(0编辑  收藏  举报

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