Django之分頁
阿新 • • 發佈：2018-05-09
Django 分頁一、Django的分頁器（paginator）
1、批量導入數據
book_list = []
for i in range(100):
book_obj = Book(title="Book_%s" % i, price=i * i)
book_list.append(book_obj)
Book.objects.bulk_create(book_list)2、分頁用法
views.py文件內容:
from django.shortcuts import render,HttpResponse
from app01.models import *
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger
def index(request):
'''
分頁器的使用:
book_list=Book.objects.all()
paginator = Paginator(book_list, 10)
print("count:",paginator.count) #數據總數
print("num_pages",paginator.num_pages) #總頁數
print("page_range",paginator.page_range) #頁碼的列表
page1=paginator.page(1) #第1頁的page對象
for i in page1: #遍歷第1頁的所有數據對象
print(i)
print(page1.object_list) #第1頁的所有數據
page2=paginator.page(2)
print(page2.has_next()) #是否有下一頁
print(page2.next_page_number()) #下一頁的頁碼
print(page2.has_previous()) #是否有上一頁
print(page2.previous_page_number()) #上一頁的頁碼
# 拋錯
#page=paginator.page(12) # error:EmptyPage
#page=paginator.page("z") # error:PageNotAnInteger
'''
book_list=Book.objects.all()
paginator = Paginator(book_list, 10) #每頁顯示10條數據
page = request.GET.get('page',1) #當前的所在的頁數
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})index.html文件內容：
<!DOCTYPE html>
<html>
<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>
<h4>分頁器</h4>
<ul>
{% for book in book_list %}
<li>{{ book.title }} -----{{ book.price }}</li>
{% endfor %}
</ul>
<ul id="pager">
{% if book_list.has_previous %}
<li><a href="/index/?page={{ book_list.previous_page_number }}">上一頁</a></li>
{% else %}
<li class="previous disabled"><a href="#">上一頁</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><a href="/index/?page={{ num }}">{{ num }}</a></li>
{% endif %}
{% endfor %}
{% if book_list.has_next %}
<li><a href="/index/?page={{ book_list.next_page_number }}">下一頁</a></li>
{% else %}
<li class="next disabled"><a href="#">下一頁</a></li>
{% endif %}
</ul>
</div>
</body>
</html>3、對顯示大量頁碼列表進行優化
def index(request):
book_list=Book.objects.all()
paginator = Paginator(book_list, 15)
page = request.GET.get('page',1)
currentPage=int(page)
# 如果頁數十分多時，換另外一種顯示方式
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())二、自定義分頁
"""
分頁組件使用示例：
obj = Pagination(request.GET.get('page',1),len(USER_LIST),request.path_info)
page_user_list = USER_LIST[obj.start:obj.end]
page_html = obj.page_html()
return render(request,'index.html',{'users':page_user_list,'page_html':page_html})
"""
class Pagination(object):
def __init__(self,current_page,all_count,base_url,per_page_num=2,pager_count=11):
"""
封裝分頁相關數據
:param current_page: 當前頁
:param all_count: 數據庫中的數據總條數
:param per_page_num: 每頁顯示的數據條數
:param base_url: 分頁中顯示的URL前綴
:param pager_count: 最多顯示的頁碼個數
"""
try:
current_page = int(current_page)
except Exception as e:
current_page = 1
if current_page <1:
current_page = 1
self.current_page = current_page
self.all_count = all_count
self.per_page_num = per_page_num
self.base_url = base_url
# 總頁碼
all_pager, tmp = divmod(all_count, per_page_num)
if tmp:
all_pager += 1
self.all_pager = all_pager
self.pager_count = pager_count
self.pager_count_half = int((pager_count - 1) / 2)
@property
def start(self):
return (self.current_page - 1) * self.per_page_num
@property
def end(self):
return self.current_page * self.per_page_num
def page_html(self):
# 如果總頁碼 < 11個：
if self.all_pager <= self.pager_count:
pager_start = 1
pager_end = self.all_pager + 1
# 總頁碼 > 11
else:
# 當前頁如果<=頁面上最多顯示11/2個頁碼
if self.current_page <= self.pager_count_half:
pager_start = 1
pager_end = self.pager_count + 1
# 當前頁大於5
else:
# 頁碼翻到最後
if (self.current_page + self.pager_count_half) > self.all_pager:
pager_end = self.all_pager + 1
pager_start = self.all_pager - self.pager_count + 1
else:
pager_start = self.current_page - self.pager_count_half
pager_end = self.current_page + self.pager_count_half + 1
page_html_list = []
first_page = '<li><a href="%s?page=%s">首頁</a></li>' % (self.base_url,1,)
page_html_list.append(first_page)
if self.current_page <= 1:
prev_page = '<li><a href="#">上一頁</a></li>'
else:
prev_page = '<li><a href="%s?page=%s">上一頁</a></li>' % (self.base_url,self.current_page - 1,)
page_html_list.append(prev_page)
for i in range(pager_start, pager_end):
if i == self.current_page:
temp = '<li><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_pager:
next_page = '<li><a href="#">下一頁</a></li>'
else:
next_page = '<li><a href="%s?page=%s">下一頁</a></li>' % (self.base_url,self.current_page + 1,)
page_html_list.append(next_page)
last_page = '<li><a href="%s?page=%s">尾頁</a></li>' % (self.base_url,self.all_pager,)
page_html_list.append(last_page)
return ''.join(page_html_list)Django之分頁