一 Django的分页器(paginator)简介
在页面显示分页数据，需要用到Django分页器组件，Django提供了一些类来帮助您管理分页数据 - 即分布在多个页面上的数据，带有“上一页/下一页”链接
示例
>>> from django.core.paginator import Paginator >>> objects = [‘john‘, ‘paul‘, ‘george‘, ‘ringo‘] >>> p = Paginator(objects, 2) >>> p.count 4 >>> p.num_pages 2 >>> type(p.page_range) <class ‘range_iterator‘> >>> p.page_range range(1, 3) >>> page1 = p.page(1) >>> page1 <Page 1 of 2> >>> page1.object_list [‘john‘, ‘paul‘] >>> page2 = p.page(2) >>> page2.object_list [‘george‘, ‘ringo‘] >>> page2.has_next() False >>> page2.has_previous() True >>> page2.has_other_pages() True >>> page2.next_page_number() Traceback (most recent call last): ... EmptyPage: That page contains no results >>> page2.previous_page_number() 1 >>> page2.start_index() # The 1-based index of the first item on this page 3 >>> page2.end_index() # The 1-based index of the last item on this page 4 >>> p.page(0) Traceback (most recent call last): ... EmptyPage: That page number is less than 1 >>> p.page(3) Traceback (most recent call last): ... EmptyPage: That page contains no results
Paginator对象： paginator = Paginator(user_list, 10) # per_page: 每页显示条目数量 # count: 数据总个数 # num_pages:总页数 # page_range:总页数的索引范围，如: (1,10),(1,200) # page: page对象 page对象：page=paginator.page(1) # has_next 是否有下一页 # next_page_number 下一页页码 # has_previous 是否有上一页 # previous_page_number 上一页页码 # object_list 分页之后的数据列表 # number 当前页 # paginator paginator对象
二 应用View层
from django.shortcuts import render,HttpResponse
# Create your views here.
from app01.models import *
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
def index(request):
‘‘‘
批量导入数据:
Booklist=[]
for i in range(100):
Booklist.append(Book(title="book"+str(i),price=30+i*i))
Book.objects.bulk_create(Booklist)
‘‘‘
‘‘‘
分页器的使用:
book_list=Book.objects.all()
paginator = Paginator(book_list, 10)
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
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)
print(page1.object_list) #第1页的所有数据
page2=paginator.page(2)
print(page2.has_next()) #是否有下一页
print(page2.next_page_number()) #下一页的页码
print(page2.has_previous()) #是否有上一页
print(page2.previous_page_number()) #上一页的页码
# 抛错
#page=paginator.page(12) # error:EmptyPage
#page=paginator.page("z") # error:PageNotAnInteger
‘‘‘
book_list=Book.objects.all()
paginator = Paginator(book_list, 10)
page = request.GET.get(‘page‘,1)
currentPage=int(page)
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",{"book_list":book_list,"paginator":paginator,"currentPage":currentPage})
三 模板层 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>
<div class="container">
<h4>分页器</h4>
<ul>
{% for book in book_list %}
<li>{{ book.title }} -----{{ book.price }}</li>
{% endfor %}
</ul>
<ul class="pagination" id="pager">
{% if book_list.has_previous %}
<li class="previous"><a href="/index/?page={{ book_list.previous_page_number }}">上一页</a></li>
{% else %}
<li class="previous disabled"><a href="#">上一页</a></li>
{% endif %}
{% for num in paginator.page_range %}
{% if num == currentPage %}
<li class="item active"><a href="/index/?page={{ num }}">{{ num }}</a></li>
{% else %}
<li class="item"><a href="/index/?page={{ num }}">{{ num }}</a></li>
{% endif %}
{% endfor %}
{% if book_list.has_next %}
<li class="next"><a href="/index/?page={{ book_list.next_page_number }}">下一页</a></li>
{% else %}
<li class="next disabled"><a href="#">下一页</a></li>
{% endif %}
</ul>
</div>
</body>
</html>
四 扩展
核心逻辑
‘‘‘
显示左5，右5，总共11个页，
1 如果总页码大于11
1.1 if 当前页码减5小于1，要生成1到12的列表（顾头不顾尾，共11个页码）
page_range=range(1,12)
1.2 elif 当前页码+5大于总页码，生成当前页码减10，到当前页码加1的列表（顾头不顾尾，共11个页码）
page_range=range(paginator.num_pages-10,paginator.num_pages+1)
1.3 else 生成当前页码-5，到当前页码+6的列表
page_range=range(current_page_num-5,current_page_num+6)
2 其它情况，生成的列表就是pageinator的page_range
page_range=paginator.page_range
‘‘‘
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>11:
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())
def page_test(request):
# book_list=[]
# for i in range(100):
# book=Book(name=‘book%s‘%i,price=10+i,pub_date=‘2018-09-18‘,publish_id=1)
# book_list.append(book)
# Book.objects.bulk_create(book_list,10)
book_list=Book.objects.all()
# 生成paginator对象，传入书籍列表，每页10条数据
paginator=Paginator(book_list,3)
# 总页码数
print(paginator.num_pages)
# 页码列表
print(paginator.page_range)
# 总数据
print(paginator.count)
# 获取页面传来的页码
current_page=int(request.GET.get(‘page‘,1))
page_range=[]
# 左5 右5
# 获取页面传来的页码的page对象
try:
page=paginator.page(current_page)
# print(page.has_next()) #是否有下一页
# print(page.next_page_number()) #下一页的页码
# print(page.has_previous()) #是否有上一页
# print(page.previous_page_number()) #上一页的页码
# 循环打印出当页对象
for i in page:
print(i)
except Exception as e:
current_page=1
page = paginator.page(1)
if paginator.num_pages>11:
if current_page+5>paginator.num_pages:
page_range=range(paginator.num_pages-10,paginator.num_pages+1)
elif current_page-5<1:
page_range=range(1,12)
else:
page_range=range(current_page-5,current_page+6)
else:
page_range=paginator.page_range
return render(request,‘page_test.html‘,locals())
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.min.css">
<title>Title</title>
</head>
<body>
<ul>
{% for foo in page %}
<li>{{ foo.name }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
{% if page.has_previous %}
<li>
<a href="/page_test/?page={{ 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 foo in page_range %}
{% if current_page == foo %}
<li class="active"><a href="/page_test/?page={{ foo }}">{{ foo }}</a></li>
{% else %}
<li><a href="/page_test/?page={{ foo }}">{{ foo }}</a></li>
{% endif %}
{% endfor %}
{% if page.has_next %}
<li>
<a href="/page_test/?page={{ 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="Next">
<span aria-hidden="true">下一页</span>
</a>
</li>
{% endif %}
</ul>
</nav>
</body>
</html>
原文地址：https://www.cnblogs.com/chen464863847/p/9649517.html
时间： 2024-11-02 23:43:05