Django——母版,自定义simple-tag函数,分页,cookie

templates

1、母版

extends方法

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>{% block title %} {% endblock %}</title>
 6     <link rel="stylesheet" href="/static/commons.css" />
 7     <style>
 8         .pg-header{
 9             height: 50px;
10             background-color: seashell;
11             color: green;
12         }
13     </style>
14     {% block css %} {% endblock %}
15 </head>
16 <body>
17     <div class="pg-header">小男孩管理</div>
18     <div>
19         <a>asdf</a>
20         <a id="">asdf</a>
21         <a>asdf</a>
22         <a>asdf</a>
23         <a>asdf</a>
24     </div>
25     <iframe src="/"></iframe>
26 </body>
27 </html>
View Code

include方法

引入母版文件

 1 {% extends 'master.html' %}
 2 {% block title %}用户管理{% endblock %}
 3 {% block content %}
 4     <h1>用户管理</h1>
 5     <ul>
 6         {% for i in u %}
 7             <li>{{ i }}</li>
 8         {% endfor %}
 9     </ul>
10     {% for i in u %}
11         {% include 'tag.html' %}
12     {% endfor %}
13 {% endblock %}
14 
15 {% block css %}
16     <style>
17         body{
18             background-color: red;
19         }
20     </style>
21 {% endblock %}
22 
23 {% block js %}
24     <script>
25         //写js文件
26     </script>
27 {% endblock %}
View Code

小tips

HTML中引入CSS

<link rel = 'stylesheet' herf = 'stactic/css文件/' />

2、自定义simple-tag

官方的

{{ item.event_start|date:"Y-m-d H:i:s"}}    // 输入字符串转换成后面的时间格式
{{ bio|truncatewords:"30" }}                      // 只取输入的30个字符
{{ my_list|first|upper }}                              // 听说是第一个字符大写
{{ name|lower }}                                        // 把字符串变成小写

自定制函数步骤

1、在app目录下创建templatetags目录

2、创建任意(abc).py文件

3、创建template对象register    #一定要这么写不能改名字

from django import template
   
register = template.Library()

4、书写函数加入装饰器

a.
@register.simple_tag
def add(v1,v2,v3):
    return  v1 + v2 + v3

b.
@register.filter
def subtraction(a1,a2):
    return a1 - a2

5、在settings文件中注册app

6、在html文件顶部引入该py文件

{% load abc %}    //引入py文件 只能用{%  %}

调用函数的方法

a.  {% add 1 2 3 %}  //调用函数加传参数

b.  {{ 5|subtraction:2 }}  //函数名后面不能加空格

小tips

{% load abc %}    //先引入load
{% extends " xx.html " %}   

两种方法的优缺点

simple_tag
	缺点:
		不能作为if条件
	优点:
		参数任意

filter
	缺点:
		最多两个参数,不能加空格		
	优点:
		能作为if条件	{% if {{ 5|subtraction:2 }} %}

3.分页

我们可以通过从后端发送标签(<a herf="...">123</a>)到前端的方法实现页面的某些功能

但django默认会认为所有在页面显示的都是不安全的(为了防止XSS攻击),so有以下操作

//假设传来的参数是page_list

方法一(前端)

{{ page_list|safe }}    //加上|safe 就变成安全的

方法二(后端)

from django.utils.safestring import mark_safe

def page_list(id,arg):    #内容瞎写的,别信

    result = "<input type='text' id='%s' class='%s' />" %(id,arg,)

    return render(....,{'page_list',mark_safe(result)})    #make_safe(里面的东西就变成安全的)fenye

我们可以(在根目录建立一个文件夹utils)写一个类,里面封装着分页的操作(里面有一个bug,跳转框输入数字 不管存不存在都会跳转到那个页面)

 1 from django.utils.safestring import mark_safe
 2 
 3 
 4 class Page:
 5     def __init__(self, current_page, data_count, per_page_count=10, pager_num=7):
 6         self.current_page = current_page
 7         self.data_count = data_count
 8         self.per_page_count = per_page_count
 9         self.pager_num = pager_num
10 
11     @property   #可以直接调用不用加(),好看一些
12     def start(self):
13         return (self.current_page - 1) * self.per_page_count
14 
15     @property   
16     def end(self):
17         return self.current_page * self.per_page_count
18 
19     @property
20     def total_count(self):
21         v, y = divmod(self.data_count, self.per_page_count)
22         if y:
23             v += 1
24         return v
25 
26     def page_str(self, base_url):
27         page_list = []
28 
29         if self.total_count < self.pager_num:
30             start_index = 1
31             end_index = self.total_count + 1
32         else:
33             if self.current_page <= (self.pager_num + 1) / 2:
34                 start_index = 1
35                 end_index = self.pager_num + 1
36             else:
37                 start_index = self.current_page - (self.pager_num - 1) / 2
38                 end_index = self.current_page + (self.pager_num + 1) / 2
39                 if (self.current_page + (self.pager_num - 1) / 2) > self.total_count:
40                     end_index = self.total_count + 1
41                     start_index = self.total_count - self.pager_num + 1
42 
43         if self.current_page == 1:
44             prev = '<a class="page" href="javascript:void(0);">上一页</a>'
45         else:
46             prev = '<a class="page" href="%s?p=%s">上一页</a>' % (base_url, self.current_page - 1,)
47         page_list.append(prev)
48 
49         for i in range(int(start_index), int(end_index)):
50             if i == self.current_page:
51                 temp = '<a class="page active" href="%s?p=%s">%s</a>' % (base_url, i, i)
52             else:
53                 temp = '<a class="page" href="%s?p=%s">%s</a>' % (base_url, i, i)
54             page_list.append(temp)
55 
56         if self.current_page == self.total_count:
57             nex = '<a class="page" href="javascript:void(0);">下一页</a>'
58         else:
59             nex = '<a class="page" href="%s?p=%s">下一页</a>' % (base_url, self.current_page + 1,)
60         page_list.append(nex)
61 
62         jump = """
63         <input type='text'  /><a onclick='jumpTo(this, "%s?p=");'>GO</a>
64         <script>
65             function jumpTo(ths,base){
66                 var val = ths.previousSibling.value;
67                 location.href = base + val;
68             }
69         </script>
70         """ % (base_url,)
71 
72         page_list.append(jump)
73 
74         page_str = mark_safe("".join(page_list))
75 
76         return page_str
分页的类,以后要用

直接调用类里面的方法

from  utils import pagination
LIST = []
for i in range(500):
    LIST.append(i)

def user_list(request):
    current_page = request.GET.get('p', 1)  #1是干嘛的 ==> 第一次请求的时候默认看第一页
    current_page = int(current_page)

    page_obj = pagination.Page(current_page,len(LIST))

    data = LIST[page_obj.start:page_obj.end]

    page_str = page_obj.page_str("/user_list/")

    return render(request, 'user_list.html', {'data': data,'page_str': page_str})
 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>Title</title>
 6 </head>
 7 <body>
 8     <ul>
 9         {% for i in data %}
10             <li>{{ i }}</li>
11         {% endfor %}
12     </ul>
13 
14     <div>
15         {{ page_str }}
16     </div>
17 </body>
18 </html>
HTML

小Tips

a.
for i in range(1,5):
	print(i)
	
>>1,2,3,4

b.
herf = "javascript:void(0)" <==> herf = '#'	//啥也不干
c.
/index/?p=1

获取方法:
  page = request.GET.get('p')

4.cookie

获取cookie

request.COOKIES['key']
request.get_signed_cookie(key, default=RAISE_ERROR, salt='', max_age=None)
    参数:
        default: 默认值
           salt: 加密盐
        max_age: 后台控制过期时间

设置cookie

rep = HttpResponse(...) 或 rep = render(request, ...) 或 redirect('/index/')
 
rep.set_cookie(key,value,...)
rep.set_signed_cookie(key,value,salt='加密盐',...)
    参数:
        key,              键
        value='',         值
        max_age=None,     超时时间  #max_age=10 以s作单位
        expires=None,     超时时间(IE requires expires, so set it if hasn't been already.)
        path='/',         Cookie生效的路径,/ 表示根路径,特殊的:根路径的cookie可以被任何url的页面访问
        domain=None,      Cookie生效的域名
        secure=False,     https传输
        httponly=False    只能http协议传输,无法被JavaScript获取(不是绝对,底层抓包可以获取到也可以被覆盖)
import datetime

current_date = datetime.datetime.utcnow()

current_date = current_date+datetime.timedelta(seconds=5)   #5s

 小tips

import hashlib

m = hashlib.md5('sdcxzmvdvk')	#这里面加的就是盐

m.update('abc123')

前端也可以设置,获取cookie

<script src='/static/jquery'></script>
<script src='/static/js/jquery.cookie.js'></script>

//设置
$.cookie("key", 'value',{ path: '/' ,...});

//获取
$.cookie('key')
示例:
views.py
 1 def cookie(request):
 2     #
 3     # request.COOKIES
 4     # request.COOKIES['username111']
 5     request.COOKIES.get('username111')
 6 
 7     response = render(request,'index.html')
 8     response = redirect('/index/')
 9     # 设置cookie,关闭浏览器时失效
10     response.set_cookie('key',"value")
11     # 设置cookie, N秒后失效
12     response.set_cookie('username111',"value",max_age=10)
13     # 设置cookie, 截止时间失效
14     import datetime
15     current_date = datetime.datetime.utcnow()
16     current_date = current_date + datetime.timedelta(seconds=5)
17     response.set_cookie('username111',"value",expires=current_date)
18     response.set_cookie('username111',"value",max_age=10)
19 
20     # request.COOKIES.get('...')
21     # response.set_cookie(...)
22     obj = HttpResponse('s')
23 
24     obj.set_signed_cookie('username',"kangbazi",salt="asdfasdf")
25     request.get_signed_cookie('username',salt="asdfasdf")
26 
27     return response

login.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title></title>
 6 </head>
 7 <body>
 8     <form action="/login/" method="POST">
 9         <input type="text" name="username" placeholder="用户名" />
10         <input type="password" name="pwd" placeholder="密码" />
11         <input type="submit" />
12     </form>
13 </body>
14 </html>

index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
    <h1>欢迎登录:{{ current_user }}</h1>
</body>
</html>

 

posted @ 2017-11-08 23:38  想54256  阅读(289)  评论(0编辑  收藏  举报