Django学习---自定义分页

自定义分页

简单例子:

urls.py:

from django.contrib import admin
from django.urls import path
from django.conf.urls import url,include
from app01 import views
urlpatterns = [ url(r'^user_list/',views.user_list),
]

先固定写死数据:view.py:

LIST = []
for i in range(100):
LIST.append(i)
def user_list(request):
current_page = request.GET.get('p',1)
current_page = int(current_page)
start = (current_page-1)*10
end = current_page * 10
data = LIST[start:end]
return render(request,'user_list.html',{'li':data})

user_item.py

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<ul>
{% for item in li %}
{% include 'li.html' %}
{% endfor %}
</ul>
<div>
<a href="/user_list/?p=1">1</a>
<a href="/user_list/?p=2">2</a>
<a href="/user_list/?p=3">3</a>
</div>
</body>
</html>

显示效果:

Django学习---自定义分页

我们都知道后台穿过来的是一个字符串,如果我们把那些a标签从后台传过来,那会是什么样的呢?

views.py:

def user_list(request):
current_page = request.GET.get('p',1)
current_page = int(current_page)
start = (current_page-1)*10
end = current_page * 10
data = LIST[start:end]
page_str = '''
<a href="/user_list/?p=1">1</a>
<a href="/user_list/?p=2">2</a>
<a href="/user_list/?p=3">3</a>
'''
#return render(request,'user_list.html',{'li':data})
return render(request,'user_list.html',{'page_str':page_str,'li':data})

html.py:

<div>
{{ page_str }}
</div>

显示效果:

Django学习---自定义分页

这里可以引入一个知识:XSS攻击:即评论,输入框等输入一些脚本,for循环。

如果想要显示的话:

第一种方法:

{{ page_str|safe }}

第二种方法:

from django.utils.safestring import mark_safe
page_str = '''
<a href="/user_list/?p=1">1</a>
<a href="/user_list/?p=2">2</a>
<a href="/user_list/?p=3">3</a>
'''
page_str = mark_safe(page_str)

分页1.0版本:使用固定的列表数据,然后获得页数,

views.py:

def user_list(request):
current_page = request.GET.get('p',1)
current_page = int(current_page)
start = (current_page-1)*10
end = current_page * 10
data = LIST[start:end] all_count = len(LIST)
count,y = divmod(all_count,10)
if y:
count+=1 page_list = []
for i in range(1,count+1):
if i == current_page:
temp = '<a class="page active" href="/user_list/?p=%s">%s</a>' % (i, i)
else:
temp = '<a class="page" href="/user_list/?p=%s">%s</a>' %(i,i)
page_list.append(temp) page_str = "".join(page_list) return render(request,'user_list.html',{'page_str':page_str,'li':data})

html文件:

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
.pagination .page{
display: inline-block;
padding:5px;
background-color: seashell;
margin:5px;
}
.pagination .active{
background-color: coral;
}
</style>
</head>
<body>
<ul>
{% for item in li %}
{% include 'li.html' %}
{% endfor %}
</ul>
<div class="pagination">
{{ page_str|safe }}
</div>
</body>
</html>

显示效果:

Django学习---自定义分页

上面的分页代码我们在数据少的时候将就一下,但是如果一旦我们的数据多了,那我们如果一下子把所有的页数都显示在html中,那显然是不合适的,那我们应该要隐藏多的页数

那我们需要该for循环,显示当前页的前五个和后五个,来我们改写一些views里面的函数:

 def user_list(request):
current_page = request.GET.get('p',1)
current_page = int(current_page)
page_size = 10#页面一次显示多少条数据
page_num=11#页面显示的页数
start = (current_page-1)*page_size
end = current_page * page_size
data = LIST[start:end] all_count = len(LIST)
count,y = divmod(all_count,page_size)
if y:
count+=1 page_list = []
if count <= 11:
start_index = 1
end_index = count+1
elif count > 11:
if current_page <= (page_num+1)/2:
start_index = 1
end_index = page_num + 1
elif (current_page+(page_num-1)/2) > count :
start_index = count-page_num+1
end_index = count + 1
else:
start_index = current_page - (page_num-1)/2
end_index = current_page + (page_num+1)/2
if current_page != 1:
prev_page = '<a class="page" href="/user_list/?p=%s">上一页</a>' % (current_page-1)
page_list.append(prev_page)
for i in range(int(start_index),int(end_index)):
if i == current_page:
temp = '<a class="page active" href="/user_list/?p=%s">%s</a>' % (i, i)
else:
temp = '<a class="page" href="/user_list/?p=%s">%s</a>' %(i,i)
page_list.append(temp)
if current_page != count:
after_page = '<a class="page" href="/user_list/?p=%s">下一页</a>' % (current_page + 1)
page_list.append(after_page) jump = '''
<input type="text" /><a onclick='jumpTo(this,"/user_list/?p=");'>GO</a>
<script>
function jumpTo(ths,base){
var val = ths.previousSibling.value;
location.href = base+val;
}
</script>
'''
page_list.append(jump)
page_str = "".join(page_list) #return render(request,'user_list.html',{'li':data})
return render(request,'user_list.html',{'page_str':page_str,'li':data})

效果显示:这样就实现了上一页下一页,跳转,根据当前页数的不同显示不一样的页码

Django学习---自定义分页

我们再把这个分页功能封装成一个Page类,以后就可以通过类方法来生成分页:

 class Page(object):
def __init__(self,current_page,data_count,page_size=10,page_num=11):
self.current_page = current_page
self.data_count = data_count
self.page_size = page_size
self.page_num = page_num
@property
def start(self):
return (self.current_page-1)*self.page_size @property
def end(self):
return self.current_page * self.page_size @property
def allCount(self):
count, y = divmod(self.data_count, self.page_size)
if y:
count += 1
return count def pageList(self,count,base_url):
page_list = []
if count <= 11:
start_index = 1
end_index = count + 1
elif count > 11:
if self.current_page <= (self.page_num + 1) / 2:
start_index = 1
end_index = self.page_num + 1
elif (self.current_page + (self.page_num - 1) / 2) > count:
start_index = count - self.page_num + 1
end_index = count + 1
else:
start_index = self.current_page - (self.page_num - 1) / 2
end_index = self.current_page + (self.page_num + 1) / 2
if self.current_page != 1:
prev_page = '<a class="page" href="%s?p=%s">上一页</a>' % (base_url,self.current_page - 1)
page_list.append(prev_page)
for i in range(int(start_index), int(end_index)):
if i == self.current_page:
temp = '<a class="page active" href="%s?p=%s">%s</a>' % (base_url,i, i)
else:
temp = '<a class="page" href="%s?p=%s">%s</a>' % (base_url,i, i)
page_list.append(temp)
if self.current_page != count:
after_page = '<a class="page" href="%s?p=%s">下一页</a>' % (base_url,self.current_page + 1)
page_list.append(after_page) jump = '''
<input type="text" /><a onclick='jumpTo(this,"%s?p=");'>GO</a>
<script>
function jumpTo(ths,base){
var val = ths.previousSibling.value;
location.href = base+val;
}
</script>
''' % (base_url)
page_list.append(jump)
return page_list

然后创建一个utils,把分页类放在里面,用的时候调用就可以了

Django学习---自定义分页

调用分页类:

from utils.pagination import Page
LIST = []
for i in range(1009):
LIST.append(i)
def user_list(request):
current_page = request.GET.get('p',1)
current_page = int(current_page) page = Page(current_page,len(LIST)) data = LIST[ page.start : page.end ] count = page.allCount page_list = page.pageList(count,'/user_list/') page_str = "".join(page_list)
#return render(request,'user_list.html',{'li':data})
return render(request,'user_list.html',{'page_str':page_str,'li':data})
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