• 013---Django的分页器


    分页

    Django的分页器(paginator)

    view

     1
    from django.shortcuts import render, HttpResponse
    from app01.models import Book
    from django.core.paginator import Paginator, EmptyPage
    from app01.utils.pagination import Pagination

    def index(request): 2 # 创建数据 3 # book_list = [Book(title='Hello Python',price=price) for price in range(100)] 4 # res = Book.objects.bulk_create(book_list) # 批量创建,效率高 5 # print(res) 6 book_list = Book.objects.all() 7 # return HttpResponse('ok') 8 9 paginator = Paginator(book_list, 5) 10 11 # 打印 12 print('数据总数:', paginator.count) # 100 13 print('总页数:', paginator.num_pages) # 10 14 print('页码列表:', paginator.page_range) # range(1, 11) 15 16 current_page_num = int(request.GET.get('page', 1)) 17 if paginator.num_pages > 11: 18 if current_page_num - 5 < 1: 19 p1 = 1 20 p2 = 11 21 elif current_page_num + 5 > paginator.num_pages: 22 p1 = paginator.num_pages - 10 23 p2 = paginator.num_pages + 1 24 else: 25 p1 = current_page_num - 5 26 p2 = current_page_num + 6 27 page_range = range(p1, p2) 28 else: 29 page_range = paginator.page_range 30 try: 31 current_page = paginator.page(current_page_num) # 第几页的数据 32 except EmptyPage as e: 33 current_page = paginator.page(1) 34 return render(request, 'book_list.html', locals())
    复制代码
    
    
    <!DOCTYPE html>
    <html lang="zh_CN">
    <head>
    <meta charset="UTF-8">
    <meta http-equiv="x-ua-compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>书籍列表</title>
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/css/bootstrap.min.css"
    integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">

    </head>
    <body>


    <ul>
    {% for book in current_page %}
    <li>名称:{{ book.title }}----价格:{{ book.price }}</li>
    <br>
    {% endfor %}

    </ul>

    <nav aria-label="Page navigation">
    <ul class="pagination">
    {% 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 %}
    <li class="disabled">
    <a href="" aria-label="Previous"><span aria-hidden="true">上一页</span></a>
    </li>
    {% endif %}

    {% for num in page_range %}
    {% if current_page_num == num %}
    <li class="active"><a href="?page={{ num }}">{{ num }}</a></li>
    {% else %}
    <li><a href="?page={{ num }}">{{ num }}</a></li>
    {% endif %}
    {% endfor %}
    {% 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 %}
    <li class="disabled">
    <a href="" aria-label="Previous"><span aria-hidden="true">上一页</span></a>
    </li>
    {% endif %}

    </ul>
    </nav>


    </body>
    </html>
     

    扩展

    复制代码
    def index(request):
    
    
        book_list=Book.objects.all()
    
        paginator = Paginator(book_list, 15)
        page = request.GET.get('page',1)
        currentPage=int(page)
    
        #  如果页数十分多时,换另外一种显示方式
        if paginator.num_pages>30:
    
            if currentPage-5<1:
                pageRange=range(1,11)
            elif currentPage+5>paginator.num_pages:
                pageRange=range(currentPage-5,paginator.num_pages+1)
    
            else:
                pageRange=range(currentPage-5,currentPage+5)
    
        else:
            pageRange=paginator.page_range
    
    
        try:
            print(page)
            book_list = paginator.page(page)
        except PageNotAnInteger:
            book_list = paginator.page(1)
        except EmptyPage:
            book_list = paginator.page(paginator.num_pages)
    
    
        return render(request,"index.html",locals())
    复制代码

    自定义分页器

    复制代码
    
    
    class Pagination(object):

    def __init__(self, current_page, all_count, base_url, per_page_num=10, page_count=11):
    """
    封装分页相关数据
    :param current_page: 当前页
    :param all_count: 数据库的数据总条数
    :param base_url:分页显示的url前缀
    :param per_page_num:每页显示的数据条数
    :param page_count:最多显示的页码数
    """

    try:
    current_page = int(current_page)
    except Exception as e:
    # 当输入的页码不是正经数字的时候,默认返回第一页数据
    current_page = 1

    if current_page < 1:
    current_page = 1

    self.current_page = current_page
    self.all_count = all_count
    self.base_url = base_url
    self.per_page_num = per_page_num
    self.page_count = page_count
    self.page_count_half = int(page_count) // 2

    # 总页码
    all_page, tmp = divmod(all_count, per_page_num) # 7,6 = div(90,12)
    # 如果有多余,加一页:
    if tmp:
    all_page += 1
    self.all_page = all_page

    @property
    def start(self):
    # 从哪开始
    return (self.current_page - 1) * self.per_page_num

    @property
    def end(self):
    # 到哪结束
    return self.current_page * self.per_page_num

    def page_html(self):
    # 如果总页码 <= 11:
    if self.all_page <= self.page_count:
    page_start = 1
    page_end = self.all_page + 1
    # 如果页码数 > 11:
    else:
    # 如果当前页 <= self.page_count_half
    if self.current_page <= self.page_count_half:
    page_start = 1
    page_end = self.page_count + 1
    # 当前页大于5
    else:
    # 页码翻到最后
    if (self.current_page + self.page_count_half) > self.all_page:
    page_start = self.all_page - self.page_count + 1
    page_end = self.all_page + 1
    else:
    page_start = self.current_page - self.page_count_half
    page_end = self.current_page + self.page_count_half + 1
    page_html_list = []

    first_page = '<li><a href ="%s?page=%s">首页</a></li>' % (self.base_url, 1)
    page_html_list.append(first_page)

    if self.current_page <= 1:
    prev_page = '<li class="disabled"><a href="#">上一页</a></li>'
    else:
    prev_page = '<li><a href="%s?page=%s">上一页</a></li>' % (self.base_url, self.current_page - 1,)

    page_html_list.append(prev_page)

    for i in range(page_start, page_end):
    if i == self.current_page:
    temp = '<li class="active"><a href="%s?page=%s">%s</a></li>' % (self.base_url, i, i,)
    else:
    temp = '<li><a href="%s?page=%s">%s</a></li>' % (self.base_url, i, i,)
    page_html_list.append(temp)

    if self.current_page >= self.all_page:
    next_page = '<li class="disabled"><a href="#">下一页</a></li>'
    else:
    next_page = '<li><a href="%s?page=%s">下一页</a></li>' % (self.base_url, self.current_page + 1,)
    page_html_list.append(next_page)

    last_page = '<li><a href="%s?page=%s">尾页</a></li>' % (self.base_url, self.all_page,)
    page_html_list.append(last_page)

    return ''.join(page_html_list)


     
    复制代码
    使用案例:
      
    1 def index1(request):
    2     book_list = Book.objects.all()
    3     current_page = request.GET.get('page',1)
    4     obj = Pagination(current_page,len(book_list),request.path)
    5     page_book_list = book_list[obj.start:obj.end]
    6     print(page_book_list)
    7     page_html = obj.page_html()
    8     return render(request,'book_list1.html',locals())
    
    
    
     
     1 <!DOCTYPE html>
     2 <html lang="zh_CN">
     3 <head>
     4     <meta charset="UTF-8">
     5     <meta http-equiv="x-ua-compatible" content="IE=edge">
     6     <meta name="viewport" content="width=device-width, initial-scale=1">
     7     <title>Title</title>
     8     <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/css/bootstrap.min.css"
     9           integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
    10 </head>
    11 <body>
    12 
    13 <ul>
    14     {% for book in page_book_list %}
    15         <li>名称:{{ book.title }}----价格:{{ book.price }}</li>
    16         <br>
    17     {% endfor %}
    18 
    19 </ul>
    20 
    21 <nav aria-label="Page navigation">
    22     <ul class="pagination">
    23         {{ page_html|safe }}
    24     </ul>
    25 </nav>
    26 </body>
    27 </html>
    
    
    
    
    
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  • 原文地址:https://www.cnblogs.com/xjmlove/p/9921870.html
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