Django入门（四）之Session操作、CSRF操作、自定义中间件、缓存、信号和Form组件

其他 2019-04-03 23:17:21 阅读次数: 0
版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/Dream_ya/article/details/87081838

上一篇文章>Django补充（三）之路由系统URL、自定义函数、自定义分页、Cookie操作、FBV和CBV

一、本机环境

操作系统：rhel7.3
Python版本：python3.6
Django版本：Django-2.1.5

[root@python _Django]# tree newproject
newproject
├── app
│   ├── admin.py
│   ├── apps.py
│   ├── __init__.py
│   ├── migrations
│   │   ├── __init__.py
│   │   └── __pycache__
│   │       └── __init__.cpython-36.pyc
│   ├── models.py
│   ├── __pycache__
│   │   ├── admin.cpython-36.pyc
│   │   ├── __init__.cpython-36.pyc
│   │   └── models.cpython-36.pyc
│   ├── tests.py
│   └── views.py
├── db.sqlite3
├── manage.py
├── newproject
│   ├── __init__.py
│   ├── __pycache__
│   │   ├── __init__.cpython-36.pyc
│   │   ├── settings.cpython-36.pyc
│   │   ├── urls.cpython-36.pyc
│   │   └── wsgi.cpython-36.pyc
│   ├── settings.py
│   ├── urls.py
│   └── wsgi.py
├── static
│   ├── jquery-1.12.4.min.js
│   └── jquery.cookie-1.4.1.min.js
└── templates

二、Session操作

1、Session介绍

基于Cookie做验证时：敏感信息不适合放在cookie中！！！

  • Cookie是保存在用户浏览器端的键值对

  • Session是保存在服务器端的键值对

2、实现Session登陆

（1）配置urls.py
[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
]
（2）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse

def login(request):
    if request.method == "GET":
        return render(request, "login.html")
    elif request.method == "POST":
        user = request.POST.get('user')
        pwd = request.POST.get('pwd')
        if user == "dream" and pwd == '1':
            ### 生成随机字符串，写到用户浏览器cookie
            ### 保存在session中，在随机字符串对应的字典中设置相关内容
            request.session['username'] = user
            request.session['is_login'] = True
            return redirect('/index')
        else:
            return render(request, 'login.html')
            
def index(request):
    ### 获取session中的值
    if request.session.get('is_login', None):
        return HttpResponse(request.session['username'])
    else:
        return HttpResponse('404 not Found')
（3）配置HTML
[root@python newproject]# vim templates/login.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/login/" method="POST">
    <label>用户名：</label>
    <input type="text" name="user" />
    <br/>
    <label>密码：</label>
    <input type="password" name="pwd" />
    <input type="submit" value="提交" />
</form>
</body>
</html>
（4）访问
http://10.10.10.111:8000/login/

3、添加注销及session清除

（1）session参数
### 用户session随机字符串
request.session.session_key

### 将所有Session失效日期小于当前日期的数据删除
request.session.clear_expired()

### 检查用户session的随机字符串是否存在在数据库（默认）
request.session.exsists("session_key")

### 删除当前用户的所有session数据
request.session.delete("session_key")

### 删除某一条session数据
del request.session['k1']

### clear等同于
request.session.clear() ==>> request.session.delete(request.session.session_key)
（2）配置urls.py
[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
    path('logout/', views.logout),
]
（3）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse

def login(request):
    if request.method == "GET":
        return render(request, "login.html")
    elif request.method == "POST":
        user = request.POST.get('user')
        pwd = request.POST.get('pwd')
        if user == "dream" and pwd == '1':
            ### 生成随机字符串，写到用户浏览器cookie
            ### 保存在session中，在随机字符串对应的字典中设置相关内容
            request.session['username'] = user
            request.session['is_login'] = True
            return redirect('/index')
        else:
            return render(request, 'login.html')

def index(request):
    ### 获取session中的值
    if request.session.get('is_login', None):
        return render(request, 'index.html', {'username': request.session['username']})
    else:
        return HttpResponse('404 not Found')

def logout(request):
    ### 清除session
    request.session.clear()
    return redirect('/login/')
（4）配置HTML
[root@python newproject]# vim templates/index.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <!--获取二种方式-->
    <h1>欢迎登陆：{{ username }},{{ request.session.username }}</h1>
    <a href="/logout">logout</a>
</body>
</html>
（5）访问
http://10.10.10.111:8000/login/

4、设置登录超时时间

（1）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse

def login(request):
    if request.method == "GET":
        return render(request, "login.html")
    elif request.method == "POST":
        user = request.POST.get('user')
        pwd = request.POST.get('pwd')
        if user == "dream" and pwd == '1':
            ### 生成随机字符串，写到用户浏览器cookie
            ### 保存在session中，在随机字符串对应的字典中设置相关内容
            request.session['username'] = user
            request.session['is_login'] = True
            if request.POST.get('savaValue', None) == '1':
                ### 设置超时时间为6s
                request.session.set_expiry(6)
            return redirect('/index')
        else:
            return render(request, 'login.html')

def index(request):
    ### 获取session中的值
    if request.session.get('is_login', None):
        return render(request, 'index.html', {'username': request.session['username']})
    else:
        return HttpResponse('404 not Found')

def logout(request):
    ### 清除session
    request.session.clear()
    return redirect('/login/')
（2）配置HTML
[root@python newproject]# vim templates/login.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/login/" method="POST">
    <label>用户名：</label>
    <input type="text" name="user" />
    <br/>
    <label>密码：</label>
    <input type="password" name="pwd" />
    <br/>
    <input type="checkbox" name="savaValue" value="1" />6秒免登陆
    <input type="submit" value="提交" />
</form>
</body>
</html>
（3）访问

我们可以发现登陆后，6s后不能访问（即使我们在使用网站），这样在日常使用中是不科学的，我应该刷新网站会使网页超时时间也进行自动更改为当前时间后的6s！！！

http://10.10.10.111:8000/login/

5、登录超时时间自动刷新

（1）Session默认配置说明
配置文件中（settings.py ）设置默认操作（通用配置）：
		SESSION_COOKIE_NAME ＝ "sessionid"        ###Session的cookie保存在浏览器上时的key，即：sessionid＝随机字符串（默认）
		SESSION_COOKIE_PATH ＝ "/"                ###Session的cookie保存的路径（默认）
		SESSION_COOKIE_DOMAIN = None              ###Session的cookie保存的域名（默认）
		SESSION_COOKIE_SECURE = False             ###是否Https传输cookie（默认）
		SESSION_COOKIE_HTTPONLY = True            ###是否Session的cookie只支持http传输（默认）
		SESSION_COOKIE_AGE = 1209600              ###Session的cookie失效日期（2周）（默认）
		SESSION_EXPIRE_AT_BROWSER_CLOSE = False   ###是否关闭浏览器使得Session过期（默认）
		# set_cookie('k',123)
		SESSION_SAVE_EVERY_REQUEST = False        ###是否每次请求都保存Session，默认修改之后才保存（默认）
（2）配置settings.py
[root@python newproject]# vim newproject/settings.py     ###在末尾添加此条即可
SESSION_SAVE_EVERY_REQUEST = True
（3）访问

访问可以发现我们在使用时，只要刷新页面页面就不会超时，6s不刷新页面便会超时！！！

http://10.10.10.111:8000/login/

6、设置Session保存位置（内部自带五种）

在settings.py中加入！！！

（1）数据库（默认）
SESSION_ENGINE = 'django.contrib.sessions.backends.db'
（2）缓存
SESSION_ENGINE = 'django.contrib.sessions.backends.cache'
SESSION_CACHE_ALIAS = 'default'       ###使用的缓存别名（默认内存缓存，也可以是memcache）

eg.连接Memcache

[root@python newproject]# vim newproject/settings.py      ###末尾加入即可
SESSION_ENGINE = 'django.contrib.sessions.backends.cache'
SESSION_CACHE_ALIAS = 'default'

### 里面可以加多个连接
CACHES = {
	'default': {
		'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
		'LOCATION': [
			'10.10.10.1:11211',
			'10.10.10.2:11211',
		]
    }
}
（3）文件
SESSION_ENGINE = 'django.contrib.sessions.backends.file'
### 缓存文件路径，None表示使用tempfile模块获取一个临时地址tempfile.gettempdir()
SESSION_FILE_PATH = None
（4）缓存+数据库
SESSION_ENGINE = 'django.contrib.sessions.backends.cache_db'
（5）加密cookie
SESSION_ENGINE = 'django.contrib.sessions.backends.signed_cookies'

三、CSRF操作

注意：这样是全局CSRF，所有都需要进过认证！！！

1、设置全局CSRF（配置settings.py）

[root@python newproject]# vim newproject/settings.py      ###取消注释

在这里插入图片描述

2、CSRF简介

防止跨站请求伪造，黑客可以伪造用户访问，因此通过用户自己的cookie来通过安全验证，在用户HTTP请求中加入随机token进行验证！！！

3、Form表单提交方式（csrf_token）

（1）配置HTML
[root@python newproject]# vim templates/login.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/login/" method="POST">
    {% csrf_token %}
    <label>用户名：</label>
    <input type="text" name="user" />
    <br/>
    <label>密码：</label>
    <input type="password" name="pwd" />
    <br/>
    <input type="checkbox" name="savaValue" value="1" />6秒免登陆
    <input type="submit" value="提交" />
</form>
</body>
</html>

可以发现我们现在在input中不输入内容提交也不会报错！！！
在这里插入图片描述

4、Ajax提交方式

（1）单个写法
[root@python newproject]# vim templates/login.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/login/" method="POST">
    {% csrf_token %}
    <label>用户名：</label>
    <input type="text" name="user" />
    <br/>
    <label>密码：</label>
    <input type="password" name="pwd" />
    <br/>
    <input type="checkbox" name="savaValue" value="1" />6秒免登陆
    <input type="submit" value="提交" />
    <input id="1" type="button" value="Ajax提交">
</form>
<script src="/static/jquery-1.12.4.min.js"></script>
<script src="/static/jquery.cookie-1.4.1.min.js"></script>
<script>
    $(function () {
        $('#1').click(function () {
            $.ajax({
                url: '/login/',
                type: 'POST',
                data: {'user': 'dream', 'pwd': '1'},
                // 默认收到的消息会加HTTP_，且X-CSRFtoken中不能有_
                headers: {'X-CSRFtoken': $.cookie('csrftoken')},
                success: function (arg) {

                }
            })
        });
    })
</script>
</body>
</html>
（2）多个写法（优化）
[root@python newproject]# vim templates/login.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/login/" method="POST">
    {% csrf_token %}
    <label>用户名：</label>
    <input type="text" name="user" />
    <br/>
    <label>密码：</label>
    <input type="password" name="pwd" />
    <br/>
    <input type="checkbox" name="savaValue" value="1" />6秒免登陆
    <input type="submit" value="提交" />
    <input id="1" type="button" value="Ajax提交">
</form>
<script src="/static/jquery-1.12.4.min.js"></script>
<script src="/static/jquery.cookie-1.4.1.min.js"></script>
<script>
    $(function () {
        // 把header统一写好，多个ajax提交也不用重写
        $.ajaxSetup({
           beforeSend: function (xhr, settings) {
               xhr.setRequestHeader('X-CSRFtoken', $.cookie('csrftoken'));
           }
        });

        $('#1').click(function () {
            $.ajax({
                url: '/login/',
                type: 'POST',
                data: {'user': 'dream', 'pwd': '1'},
                // 默认收到的消息会加HTTP_，且X-CSRFtoken中不能有_
                // headers: {'X-CSRFtoken': $.cookie('csrftoken')},
                success: function (arg) {

                }
            })
        });
    })
</script>
</body>
</html>

5、局部CSRF设置

### 在views中通过from导入，然后装饰设置函数
from django.views.decorators.csrf import csrf_exempt,csrf_protect
@csrf_protect        ###当前函数设置CSRF，我就把setting中的CSRF注释掉
@csrf_exempt         ###当前函数取消CSRF,把setting中的CSRF打开

6、CSRF判断

[root@python newproject]# vim templates/login.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/login/" method="POST">
    {% csrf_token %}
    <label>用户名：</label>
    <input type="text" name="user" />
    <br/>
    <label>密码：</label>
    <input type="password" name="pwd" />
    <br/>
    <input type="checkbox" name="savaValue" value="1" />6秒免登陆
    <input type="submit" value="提交" />
    <input id="1" type="button" value="Ajax提交">
</form>
<script src="/static/jquery-1.12.4.min.js"></script>
<script src="/static/jquery.cookie-1.4.1.min.js"></script>
<script>
    // 这样我们可以实现不符合要求的提交不进行CSRF
    $(function () {
        function csrfSafeMethod(method){
            return (/^(GET|HEAD|OPTIONS|TRACE)$/.test(method))
        };
        
        // 把header统一写好，多个ajax提交也不用重写
        $.ajaxSetup({
           beforeSend: function (xhr, settings) {
               // xhr.setRequestHeader('X-CSRFtoken', $.cookie('csrftoken'));
               if (!csrfSafeMethod(settings.type) && !this.crossDomain){
                   xhr.setRequestHeader('X-CSRFtoken', $.cookie('csrftoken'));
               }
           }
        });

        $('#1').click(function () {
            $.ajax({
                url: '/login/',
                type: 'POST',
                data: {'user': 'dream', 'pwd': '1'},
                // 默认收到的消息会加HTTP_
                // headers: {'X-CSRFtoken': $.cookie('csrftoken')},
                success: function (arg) {

                }
            })
        });
    })
</script>
</body>
</html>

四、自定义中间件

1、process_request和process_response操作

通过process_request发送，process_response回应，中间件就是一层一层传输，然后在在一层一层回应！！！

（1）配置m1.py
[root@python newproject]# mkdir Middle
[root@python newproject]# vim Middle/m1.py
#!/usr/bin/env python
# coding:utf-8
from django.utils.deprecation import MiddlewareMixin
class Middle1(MiddlewareMixin):
    ### 请求进来经过
    def process_request(self, request):
        print ('process_request Middle1')

    def process_response(self, request, response):
        print ('process_response Middle1')
        return response

class Middle2(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle2')

    def process_response(self, request, response):
        print ('process_response Middle2')
        return response

class Middle3(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle3')

    def process_response(self, request, response):
        print ('process_response Middle3')
        return response
（2）加入test网址
[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
    path('logout/', views.logout),
    path('test/', views.test),
]

[root@python newproject]# vim app/views.py       ###在末尾加入
def test(request):
    print ('test')
    return HttpResponse('OK')

[root@python newproject]# vim newproject/settings.py

在这里插入图片描述

（3）访问并查看结果
http://10.10.10.111:8000/test/

在这里插入图片描述

2、process_view操作

process_request后，从头开始执行process_view！！！

（1）配置m1.py
[root@python newproject]# vim Middle/m1.py
#!/usr/bin/env python
# coding:utf-8
from django.utils.deprecation import MiddlewareMixin
class Middle1(MiddlewareMixin):
    ### 请求进来经过
    def process_request(self, request):
        print ('process_request Middle1')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle1")

    def process_response(self, request, response):
        print ('process_response Middle1')
        return response

class Middle2(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle2')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle2")

    def process_response(self, request, response):
        print ('process_response Middle2')
        return response

class Middle3(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle3')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle3")
        
    def process_response(self, request, response):
        print ('process_response Middle3')
        return response
（2）访问并查看结果
http://10.10.10.111:8000/test/

在这里插入图片描述

（3）获取值view_func_args

<1> 配置urls.py

[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path, re_path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
    path('logout/', views.logout),
    re_path('test/(\d+)', views.test),
]

<2> 配置m1.py

[root@python newproject]# vim Middle/m1.py
#!/usr/bin/env python
# coding:utf-8
from django.utils.deprecation import MiddlewareMixin
class Middle1(MiddlewareMixin):
    ### 请求进来经过
    def process_request(self, request):
        print ('process_request Middle1')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle1")

    def process_response(self, request, response):
        print ('process_response Middle1')
        return response

class Middle2(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle2')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle2")
        print (view_func, view_func_args, view_func_kwargs)

    def process_response(self, request, response):
        print ('process_response Middle2')
        return response

class Middle3(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle3')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle3")

    def process_response(self, request, response):
        print ('process_response Middle3')
        return response

<3> 访问并查看结果

http://10.10.10.111:8000/test/1

在这里插入图片描述

（4）获取值view_func_kwargs

<1> 配置urls.py

[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path, re_path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
    path('logout/', views.logout),
    re_path('test/(?P<nid>\d+)', views.test),
]

<2> 访问并查看结果

http://10.10.10.111:8000/test/1

在这里插入图片描述

3、process_exception操作

不会直接运行当views中有报错才会运行！！！

（1）配置m1.py
[root@python newproject]# vim Middle/m1.py
#!/usr/bin/env python
# coding:utf-8
from django.utils.deprecation import MiddlewareMixin
class Middle1(MiddlewareMixin):
    ### 请求进来经过
    def process_request(self, request):
        print ('process_request Middle1')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle1")

    def process_response(self, request, response):
        print ('process_response Middle1')
        return response

class Middle2(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle2')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle2")
        print (view_func, view_func_args, view_func_kwargs)

    def process_response(self, request, response):
        print ('process_response Middle2')
        return response

class Middle3(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle3')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle3")

    def process_response(self, request, response):
        print ('process_response Middle3')
        return response

    ### 添加process_exception
    def process_exception(self, request, exception):
        print ('process_exception Middle3')
（2）配置views.py
[root@python newproject]# vim app/views.py
def test(request,nid):
    ### 此处报错
    int('dreamya')
    print ('test')
    return HttpResponse('OK')
（3）访问并查看结果
http://10.10.10.111:8000/test/1

在这里插入图片描述

（4）进行错误处理

<1> 配置m1.py

[root@python newproject]# vim Middle/m1.py
#!/usr/bin/env python
# coding:utf-8
from django.utils.deprecation import MiddlewareMixin
from django.shortcuts import HttpResponse
class Middle1(MiddlewareMixin):
    ### 请求进来经过
    def process_request(self, request):
        print ('process_request Middle1')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle1")

    def process_response(self, request, response):
        print ('process_response Middle1')
        return response

class Middle2(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle2')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle2")
        print (view_func, view_func_args, view_func_kwargs)

    def process_response(self, request, response):
        print ('process_response Middle2')
        return response

class Middle3(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle3')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle3")

    def process_response(self, request, response):
        print ('process_response Middle3')
        return response

    def process_exception(self, request, exception):
        # print ('process_exception Middle3')
        if isinstance(exception, ValueError):
            return HttpResponse("异常错误！！！")

<2> 访问并查看结果

http://10.10.10.111:8000/test/1

在这里插入图片描述
在这里插入图片描述

4、process_template_response操作

如果Viess中的函数中返回的对象中有render方法，就会运行！！！

（1）配置views.py
[root@python newproject]# vim app/views.py
class F:
    def render(self):
        return HttpResponse('OK')

def test(request,nid):
    print ('test')
    return F()
（2）配置m1.py
[root@python newproject]# vim Middle/m1.py
#!/usr/bin/env python
# coding:utf-8
from django.utils.deprecation import MiddlewareMixin
from django.shortcuts import HttpResponse
class Middle1(MiddlewareMixin):
    ### 请求进来经过
    def process_request(self, request):
        print ('process_request Middle1')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle1")

    def process_response(self, request, response):
        print ('process_response Middle1')
        return response

class Middle2(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle2')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle2")
        print (view_func, view_func_args, view_func_kwargs)

    def process_response(self, request, response):
        print ('process_response Middle2')
        return response

class Middle3(MiddlewareMixin):
    def process_request(self, request):
        print ('process_request Middle3')

    def process_view(self, request, view_func, view_func_args, view_func_kwargs):
        print ("process_view Middle3")

    def process_response(self, request, response):
        print ('process_response Middle3')
        return response

    def process_exception(self, request, exception):
        # print ('process_exception Middle3')
        if isinstance(exception, ValueError):
            return HttpResponse("异常错误！！！")

    def process_template_response(self, request, response):
        print ('process_template_response Middle3')
        return response
（3）访问并查看结果
http://10.10.10.111:8000/test/1

在这里插入图片描述
五、缓存

1、五种配置

（1）开发调试
CACHES = {
	'default': {
		'BACKEND': 'django.core.cache.backends.dummy.DummyCache',
		'TIMEOUT': 300,       ###超时时间，默认300s
	'OPTIONS':{
		'MAX_ENTRIES': 300,          ###最大缓存个数，默认300
		'CULL_FREQUENCY': 3,      ###缓存达到最大缓存个数时，删除换出1/3，这里默认值为3
		},
		'KEY_PREFIX': '',              ###缓存key的前缀，默认为空
		'VERSION': 1,             ###缓存key版本，默认为1
		'KEY_FUNCTION':"func_name"   ###生成key的函数，默认函数会生成为->前缀:版本:key
	}
}

### 自定义key
    def default_key_func(key, key_prefix, version):
        """
        Default function to generate keys.
        Constructs the key used by all other methods. By default it prepends
        the `key_prefix'. KEY_FUNCTION can be used to specify an alternate
        function with custom key making behavior.
        """
        return '%s:%s:%s' % (key_prefix, version, key)

    def get_key_func(key_func):
        """
        Function to decide which key function to use.
        Defaults to ``default_key_func``.
        """
        if key_func is not None:
            if callable(key_func):
                return key_func
            else:
                return import_string(key_func)
        return default_key_func
（2）内存
CACHES = {
	'default': {
	   'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
	   'LOCATION': 'unique-snowflake',     ###设置一个唯一值
	}
	###其他的配置和开发调试版本一样
}
（3）文件
CACHES = {
	'default': {
	    'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache',
	    'LOCATION': '/var/tmp/django_cache',  #缓存存放的路径<br>　　　　
	}
	###其他的配置和开发调试版本一样
}
（4）数据库
CACHES = {
	'default': {
	    'BACKEND': 'django.core.cache.backends.db.DatabaseCache',
	    'LOCATION': 'my_cache_table',    ###设置一个数据库存放缓存的表名
	}
	###其他的配置和开发调试版本一样
}
### 注：执行创建表命令 python manage.py createcachetable
（5）Memcache缓存

<1> 通过python-memcached模块链接

### 单台机器
CACHES = {
        'default': {
            'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
            'LOCATION': '127.0.0.1:11211',
        }
        ###其他的配置和开发调试版本一样
}
 
### 存放本地的
CACHES = {
    'default': {
        'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
        'LOCATION': 'unix:/tmp/memcached.sock',
    }
    ###其他的配置和开发调试版本一样
}  
 
### 支持集群，负载均衡
CACHES = {
    'default': {
        'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
        'LOCATION': [
            '10.10.10.1:11211',
            '10.10.10.2:11211',
           ### 设置权重
           ###('10.10.10.1:11211',10),
           ###('10.10.10.2:11211',20),
        ]   
    }
    ###其他的配置和开发调试版本一样
}

<2> 通过pylibmc模块链接

CACHES = {
    'default': {
        'BACKEND': 'django.core.cache.backends.memcached.PyLibMCCache',
        'LOCATION': '127.0.0.1:11211',
    }
}
 
CACHES = {
   'default': {
       'BACKEND': 'django.core.cache.backends.memcached.PyLibMCCache',
       'LOCATION': '/tmp/memcached.sock',
   }
}  

CACHES = {
   'default': {
       'BACKEND': 'django.core.cache.backends.memcached.PyLibMCCache',
       'LOCATION': [
           '10.10.10.1:11211',
           '10.10.10.2:11211',
       ]
   }
}

2、三种应用

（1）单独视图缓存
[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path, re_path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
    path('logout/', views.logout),
    re_path('test/(?P<nid>\d+)', views.test),
    path('cache/', views.cache),
]

[root@python newproject]# vim newproject/settings.py  ###在末尾加入
CACHES = {
    'default': {
        'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache',
        'LOCATION': os.path.join(BASE_DIR, 'cache'),
    }
}

[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse
def login(request):
    if request.method == "GET":
        return render(request, "login.html")
    elif request.method == "POST":
        user = request.POST.get('user')
        pwd = request.POST.get('pwd')
        if user == "dream" and pwd == '1':
            ### 生成随机字符串，写到用户浏览器cookie
            ### 保存在session中，在随机字符串对应的字典中设置相关内容
            request.session['username'] = user
            request.session['is_login'] = True
            if request.POST.get('savaValue', None) == '1':
                request.session.set_expiry(6)
            return redirect('/index')
        else:
            return render(request, 'login.html')

def index(request):
    ### 获取session中的值
    if request.session.get('is_login', None):
        return render(request, 'index.html', {'username': request.session['username']})
    else:
        return HttpResponse('404 not Found')

def logout(request):
    ### 清除session
    request.session.clear()
    return redirect('/login/')

class F:
    def render(self):
        return HttpResponse('OK')

def test(request,nid):
    print ('test')
    return F()
    
from django.views.decorators.cache import cache_page
### 缓存10s，默认300s
@cache_page(10)
def cache(request):
    import time
    ctime = time.time()
    return render(request, 'cache.html', { 'ctime': ctime, })

[root@python newproject]# vim templates/cache.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    {{ ctime }}
    {{ ctime }}
</body>
</html>

建立cache目录并访问

我们可以发现10s后在刷新数字才会改变！！！

[root@python newproject]# mkdir cache
http://10.10.10.111:8000/cache/
（2）局部视图缓存
[root@python newproject]# vim app/views.py     ###注释

在这里插入图片描述

[root@python newproject]# vim templates/cache.html
{% load cache %}
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    {{ ctime }}
    {% cache 10 c1 %}
        {{ ctime }}
    {% endcache %}
</body>
</html>

访问并查看结果

http://10.10.10.111:8000/cache/

在这里插入图片描述

（3）全局视图缓存
[root@python newproject]# vim newproject/settings.py    ###在中间件的首尾加入
MIDDLEWARE = [
    'django.middleware.cache.UpdateCacheMiddleware',
	...
    'django.middleware.cache.FetchFromCacheMiddleware',
]

六、信号

1、内置信号

（1）参数说明
Model signals
	pre_init               ###django的model执行其构造方法前
	post_init              ###django的model执行其构造方法后
	pre_save               ###django的model对象保存前
	post_save              ###django的model对象保存后
	pre_delete             ###django的model对象删除前
	post_delete            ###django的model对象删除后
	m2m_changed            ###django的model中使用m2m字段操作第三张表（add,remove,clear）前后
	class_prepared         ###程序启动检测已注册的app中的model类，对于每一个类

Management signals
	pre_migrate            ###执行migrate命令前
	post_migrate           ###执行migrate命令后

Request/Response signals
	request_startd         ###请求到来前
	request_finished       ###请求结束后
	got_request_exception  ###请求异常后

Test signals
	setting_changed        ###使用test测试修改配置文件时
	templates_rendered     ###使用test测试渲染模板时

Database Wrappers
	connection_created     ###创建数据库连接时
（2）实例使用
from django.core.signals import request_finished
from django.core.signals import request_started
from django.core.signals import got_request_exception
from django.db.models.signals import class_prepared
from django.db.models.signals import pre_init, post_init
from django.db.models.signals import pre_save, post_save
from django.db.models.signals import pre_delete, post_delete
from django.db.models.signals import m2m_changed
from django.db.models.signals import pre_migrate, post_migrate
from django.test.signals import setting_changed
from django.test.signals import template_rendered
from django.db.backends.signals import connection_created

def f1(sender, **kwargs):
        print("xxoo_callback")
        # print(sender,kwargs)
pre_save.connect(f1)
（3）使用方法

<1> 配置urls.py

[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path, re_path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
    path('logout/', views.logout),
    re_path('test/(?P<nid>\d+)', views.test),
    path('cache/', views.cache),
    path('signal/', views.signal),
]

<2> 配置views.py

[root@python newproject]# vim app/views.py     ###添加
def signal(request):
    from app import models
    obj = models.UserInfo(user='root')
    print('end')
    obj.save()
    return HttpResponse('OK')

<3> 配置models.py

[root@python newproject]# vim app/models.py
from django.db import models
class UserInfo(models.Model):
    user = models.CharField(max_length=32)

<4> 配置sg.py

[root@python newproject]# vim sg.py
#!/usr/bin/env python
#coding:utf-8
from django.core.signals import request_finished
from django.core.signals import request_started
from django.core.signals import got_request_exception
from django.db.models.signals import class_prepared
from django.db.models.signals import pre_init, post_init
from django.db.models.signals import pre_save, post_save
from django.db.models.signals import pre_delete, post_delete
from django.db.models.signals import m2m_changed
from django.db.models.signals import pre_migrate, post_migrate
from django.test.signals import setting_changed
from django.test.signals import template_rendered
from django.db.backends.signals import connection_created
def fun(sender,**kwargs):
    print ("fun")
    print (sender,kwargs)
pre_save.connect(fun)

[root@python newproject]# vim newproject/__init__.py
import sg

<5> 启动访问

[root@python newproject]# python manage.py makemigrations
[root@python newproject]# python manage.py migrate
[root@python newproject]# python manage.py runserver 10.10.10.111:8000
http://10.10.10.111:8000/signal/

在这里插入图片描述

2、自定义信号

自定义信号需要开发者在任意位置触发（比如报警值超过阈值触发）！！！

（1）定义信号（sg.py）
import django.dispatch
pizza_done = django.dispatch.Signal(providing_args=["toppings", "size"])
（2）注册信号（sg.py）
def callback(sender, **kwargs):
    print("callback")
    print(sender,kwargs)
pizza_done.connect(callback)
（3）触发信号（app/views.py的signal函数）
[root@python newproject]# vim app/views.py
from sg import pizza_done
pizza_done.send(sender="dream",toppings=123, size=456)

七、Form组件

1、注释掉之前的中间件

[root@python newproject]# vim newproject/settings.py

在这里插入图片描述

2、Form验证

（1）配置urls.py
[root@python newproject]# vim newproject/urls.py
from django.contrib import admin
from django.urls import path, re_path
from app import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('login/', views.login),
    path('index/', views.index),
    path('logout/', views.logout),
    re_path('test/(?P<nid>\d+)', views.test),
    path('cache/', views.cache),
    path('signal/', views.signal),
    path('fm/', views.fm),
]
（2）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse
...
from django import forms
class FM(forms.Form):
    ### 跟HTML中的name一样
    user = forms.CharField()
    pwd = forms.CharField()
    email = forms.EmailField()

def fm(request):
    if request.method == "GET":
        return render(request,'fm.html')
    elif request.method == "POST":
        obj = FM(request.POST)
        ### res为True或False
        res = obj.is_valid()
        if res:
            ### 正确信息
            print (obj.cleaned_data)
        else:
            print (obj.errors)
            print (obj.errors.as_json())
        return redirect('/fm/')
（3）配置HTMl
[root@python newproject]# vim templates/fm.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/fm/" method="POST">
        {% csrf_token %}
        <p><input type="text" name="user"></p>
        <p><input type="text" name="pwd"></p>
        <p><input type="text" name="email"></p>
        <input type="submit" value="提交">
    </form>
</body>
</html>
（4）刷新页面提交后结果
http://10.10.10.111:8000/fm/

在这里插入图片描述

3、验证并显示错误信息

（1）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse
...
from django import forms
class FM(forms.Form):
    ### 跟HTML中的name一样
    user = forms.CharField(error_messages={'required': "用户名不能为空"})
    pwd = forms.CharField(
        max_length = 12,
        min_length = 6,
        error_messages={'required': "密码不能为空", 'min_length':'密码长度不小于6', 'max_length': '密码长度不大于12'}
    )
    email = forms.EmailField(error_messages={'required': "邮箱不能为空", 'invalid':"邮箱格式错误"})

from app import models
def fm(request):
    if request.method == "GET":
        obj = FM()
        return render(request,'fm.html', {'obj': obj})
    elif request.method == "POST":
        obj = FM(request.POST)
        ### res为True或False
        res = obj.is_valid()
        if res:
            ### 正确信息
            print (obj.cleaned_data)
            ### 我们可以通过下面的方式写入到数据库中（字典格式）
            # models.UserInfo.objects.create(**obj.cleaned_data)
        else:
            # print (obj.errors['user'][0])
            # print (obj.errors.as_json())
            return render(request, 'fm.html', {'obj': obj})
        return redirect('/fm/')
（2）配置fm.html
[root@python newproject]# vim templates/fm.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/fm/" method="POST">
        {% csrf_token %}
        <!--<p><input type="text" name="user">{{ obj.errors.user.0 }}</p>-->
        <!--<p><input type="text" name="pwd">{{ obj.errors.pwd.0 }}</p>-->
        <!--<p><input type="text" name="email">{{ obj.errors.email.0 }}</p>-->
        <!--自动生成input标签-->
        <p>{{ obj.user }} {{ obj.errors.user.0 }}</p>
        <p>{{ obj.pwd }} {{ obj.errors.pwd.0 }}</p>
        <p>{{ obj.email }} {{ obj.errors.email.0 }}</p>
        <input type="submit" value="提交">
    </form>
</body>
</html>

4、简单方式（三种）

缺点：不方便自己定制！！！

（1）as_p方法
[root@python newproject]# vim templates/fm.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/fm/" method="POST">
        {% csrf_token %}
        {{ obj.as_p }}
        <input type="submit" value="提交">
    </form>
</body>
</html>
（2）as_ul方法
[root@python newproject]# vim templates/fm.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/fm/" method="POST">
        {% csrf_token %}
        {{ obj.as_ul }}
        <input type="submit" value="提交">
    </form>
</body>
</html>
（3）as_table方法
[root@python newproject]# vim templates/fm.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/fm/" method="POST">
        {% csrf_token %}
        <table>
            {{ obj.as_table }}
        </table>
        <input type="submit" value="提交">
    </form>
</body>
</html>

5、设置样式

（1）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse
...
from django import forms
from django.forms import widgets
from django.forms import fields
class FM(forms.Form):
    ### 跟HTML中的name一样
    user = fields.CharField(
        error_messages={'required': "用户名不能为空"},
        widget = widgets.Textarea(attrs={'class': 'c1',})
        )
    pwd = fields.CharField(
        max_length = 12,
        min_length = 6,
        error_messages={
            'required': "密码不能为空",
            'min_length':'密码长度不小于6',
            'max_length': '密码长度不大于12'
            },
        # widget = widgets.PasswordInput
        widget = widgets.PasswordInput(attrs={'class':"c2",}),
    )
    email = fields.EmailField(error_messages={'required': "邮箱不能为空", 'invalid':"邮箱格式错误"})

from app import models
def fm(request):
    if request.method == "GET":
        obj = FM()
        return render(request,'fm.html', {'obj': obj})
    elif request.method == "POST":
        obj = FM(request.POST)
        ### res为True或False
        res = obj.is_valid()
        if res:
            ### 正确信息
            print (obj.cleaned_data)
            # models.UserInfo.objects.create(**obj.cleaned_data)
        else:
            # print (obj.errors['user'][0])
            # print (obj.errors.as_json())
            return render(request, 'fm.html', {'obj': obj})
        return redirect('/fm/')
（2）查看结果

在这里插入图片描述

6、Django内置字段

Field
	required=True,               ###是否允许为空
	widget=None,                 ###HTML插件
	label=None,                  ###用于生成Label标签或显示内容
	initial=None,                ###初始值
	help_text='',                ###帮助信息(在标签旁边显示)
	error_messages=None,         ###错误信息 {'required': '不能为空', 'invalid': '格式错误'}
	validators=[],               ###自定义验证规则
	localize=False,              ###是否支持本地化
	disabled=False,              ###是否可以编辑
	label_suffix=None            ###Label内容后缀

CharField(Field)
	max_length=None,             ###最大长度
	min_length=None,             ###最小长度
	strip=True                   ###是否移除用户输入空白

IntegerField(Field)
	max_value=None,              ###最大值
	min_value=None,              ###最小值

FloatField(IntegerField)
    ...
 
DecimalField(IntegerField)
	max_value=None,              ###最大值
	min_value=None,              ###最小值
	max_digits=None,             ###总长度
	decimal_places=None,         ###小数位长度
 
BaseTemporalField(Field)
	input_formats=None           ###时间格式化   

DateField(BaseTemporalField)      格式：2019-02-21
TimeField(BaseTemporalField)      格式：18:12
DateTimeField(BaseTemporalField)  格式：2019-02-21 18:12
DurationField(Field)              时间间隔：%d %H:%M:%S.%f
    ...
 
RegexField(CharField)
	regex,                      ###自定制正则表达式
	max_length=None,            ###最大长度
	min_length=None,            ###最小长度
	error_message=None,         ###忽略，错误信息使用 error_messages={'invalid': '...'}
 
EmailField(CharField)      
    ...
 
FileField(Field)
	allow_empty_file=False     ###是否允许空文件
 
ImageField(FileField)      
    ...
    注：需要PIL模块，pip3 install Pillow
    以上两个字典使用时，需要注意两点：
        - form表单中 enctype="multipart/form-data"
        - view函数中 obj = MyForm(request.POST, request.FILES)
 
URLField(Field)
    ...

BooleanField(Field)  
    ...
 
NullBooleanField(BooleanField)
    ...
 
ChoiceField(Field)
    ...
	choices=(),                ###选项，如：choices = ((0,'四川'),(1,'浙江'),)
	required=True,             ###是否必填
	widget=None,               ###插件，默认select插件
	label=None,                ###Label内容
	initial=None,              ###初始值
	help_text='',              ###帮助提示
 
 
ModelChoiceField(ChoiceField)
	...                        django.forms.models.ModelChoiceField
	queryset,                  ###查询数据库中的数据
	empty_label="---------",   ###默认空显示内容
	to_field_name=None,        ###HTML中value的值对应的字段
	limit_choices_to=None      ###ModelForm中对queryset二次筛选

ModelMultipleChoiceField(ModelChoiceField)
    ...                        django.forms.models.ModelMultipleChoiceField
 
TypedChoiceField(ChoiceField)
	coerce = lambda val: val   ###对选中的值进行一次转换
	empty_value= ''            ###空值的默认值
 
MultipleChoiceField(ChoiceField)
    ...
 
TypedMultipleChoiceField(MultipleChoiceField)
	coerce = lambda val: val   ###对选中的每一个值进行一次转换
	empty_value= ''            ###空值的默认值
 
ComboField(Field)
	fields=()                  ###使用多个验证，如下：即验证最大长度20，又验证邮箱格式	                       fields.ComboField(fields=[fields.CharField(max_length=20), fields.EmailField(),])
 
MultiValueField(Field)
        PS: 抽象类，子类中可以实现聚合多个字典去匹配一个值，要配合MultiWidget使用
 
SplitDateTimeField(MultiValueField)
	input_date_formats=None,   格式列表：['%Y--%m--%d', '%m%d/%Y', '%m/%d/%y']
	input_time_formats=None    格式列表：['%H:%M:%S', '%H:%M:%S.%f', '%H:%M']
 
FilePathField(ChoiceField)     文件选项，目录下文件显示在页面中
	path,                      ###文件夹路径
	match=None,                ###正则匹配
	recursive=False,           ###递归下面的文件夹
	allow_files=True,          ###允许文件
	allow_folders=False,       ###允许文件夹
	required=True,
	widget=None,
	label=None,
	 initial=None,
	 help_text=''

GenericIPAddressField
	protocol='both',           ###both,ipv4,ipv6支持的IP格式
	unpack_ipv4=False          ###解析ipv4地址，如果是::ffff:192.0.2.1时候，可解析为192.0.2.1， PS：protocol必须为both才能启用
 
SlugField(CharField)           ###数字，字母，下划线，减号（连字符）
    ...
 
UUIDField(CharField)           ###uuid类型

7、Django内置插件

TextInput(Input)
NumberInput(TextInput)
EmailInput(TextInput)
URLInput(TextInput)
PasswordInput(TextInput)
HiddenInput(TextInput)
Textarea(Widget)
DateInput(DateTimeBaseInput)
DateTimeInput(DateTimeBaseInput)
TimeInput(DateTimeBaseInput)
CheckboxInput
Select
NullBooleanSelect
SelectMultiple
RadioSelect
CheckboxSelectMultiple
FileInput
ClearableFileInput
MultipleHiddenInput
SplitDateTimeWidget
SplitHiddenDateTimeWidget
SelectDateWidget

8、使用示例

（1）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse
...
from django import forms
from django.forms import widgets
from django.forms import fields
class FM(forms.Form):
    ### 跟HTML中的name一样
    user = fields.CharField(
        error_messages={'required': "用户名不能为空"},
        widget = widgets.Textarea(attrs={'class': 'c1',}),
        initial = 'dreamya',
        )
    pwd = fields.CharField(
        max_length = 12,
        min_length = 6,
        error_messages={
            'required': "密码不能为空",
            'min_length':'密码长度不小于6',
            'max_length': '密码长度不大于12'
            },
        # widget = widgets.PasswordInput
        widget = widgets.PasswordInput(attrs={'class':"c2",}),
    )
    email = fields.EmailField(error_messages={'required': "邮箱不能为空", 'invalid':"邮箱格式错误"})
    p = fields.FilePathField(path='app')
    province = fields.ChoiceField(
        choices=[(0,'四川'),(1,'浙江'),(2,'福建')]
    )
    province1 = fields.MultipleChoiceField(
        choices=[(0,'四川'),[1,'浙江'],(2,'福建')]
    )
    
from app import models
def fm(request):
    if request.method == "GET":
        obj = FM()
        return render(request,'fm.html', {'obj': obj})
    elif request.method == "POST":
        obj = FM(request.POST)
        ### res为True或False
        res = obj.is_valid()
        if res:
            ### 正确信息
            print (obj.cleaned_data)
            # models.UserInfo.objects.create(**obj.cleaned_data)
        else:
            # print (obj.errors['user'][0])
            # print (obj.errors.as_json())
            return render(request, 'fm.html', {'obj': obj})
        return redirect('/fm/')
（2）配置fm.html
[root@python newproject]# vim templates/fm.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/fm/" method="POST">
        {% csrf_token %}
        <p>{{ obj.user }} {{ obj.errors.user.0 }}</p>
        <p>{{ obj.pwd }} {{ obj.errors.pwd.0 }}</p>
        <p>{{ obj.email }} {{ obj.errors.email.0 }}</p>
        <input type="submit" value="提交">
    </form>
    <!--app目录下文件-->
    {{ obj.p }}
    {{ obj.province }}
    {{ obj.province1 }}
</body>
</html>

9、初始化操作

（1）配置views.py
[root@python newproject]# vim app/views.py
from django.shortcuts import render
from django.shortcuts import redirect
from django.shortcuts import HttpResponse
...
from django import forms
from django.forms import widgets
from django.forms import fields
class FM(forms.Form):
    ### 跟HTML中的name一样
    user = fields.CharField(
        error_messages={'required': "用户名不能为空"},
        widget = widgets.Textarea(attrs={'class': 'c1',}),
        initial = 'dreamya'
        )
    pwd = fields.CharField(
        max_length = 12,
        min_length = 6,
        error_messages={
            'required': "密码不能为空",
            'min_length':'密码长度不小于6',
            'max_length': '密码长度不大于12'

            },
        # widget = widgets.PasswordInput
        widget = widgets.PasswordInput(attrs={'class':"c2",}),
    )
    email = fields.EmailField(error_messages={'required': "邮箱不能为空", 'invalid':"邮箱格式错误"})
    p = fields.FilePathField(path='app')
    province = fields.ChoiceField(
        choices=[(0,'四川'),(1,'浙江'),(2,'福建')]
    )
    province1 = fields.MultipleChoiceField(
        choices=[(0,'四川'),[1,'浙江'],(2,'福建')]
    )
from app import models
def fm(request):
    if request.method == "GET":
        ### 从数据拿到数据，这里我们设置个字典相当于取出来的数据
        d = {
            'user': 'dream',
            'pwd': '123',
            'email': '[email protected]',
            'province': 1,
            'province1': [1,2],
        }
        obj = FM(initial=d)
        return render(request,'fm.html', {'obj': obj})
    elif request.method == "POST":
        obj = FM(request.POST)
        ### res为True或False
        res = obj.is_valid()
        if res:
            ### 正确信息
            print (obj.cleaned_data)
            # models.UserInfo.objects.create(**obj.cleaned_data)
        else:
            # print (obj.errors['user'][0])
            # print (obj.errors.as_json())
            return render(request, 'fm.html', {'obj': obj})
        return redirect('/fm/')
（2）配置fm.html
[root@python newproject]# vim templates/fm.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/fm/" method="POST">
        {% csrf_token %}
        <p>{{ obj.user }} {{ obj.errors.user.0 }}</p>
        <p>{{ obj.pwd }} {{ obj.errors.pwd.0 }}</p>
        <p>{{ obj.email }} {{ obj.errors.email.0 }}</p>
        <input type="submit" value="提交">
    </form>
    <!--app目录下文件-->
    {{ obj.p }}
    {{ obj.province }}
    {{ obj.province1 }}
</body>
</html>
（3）查看结果

在这里插入图片描述
下一篇文章>Django入门（五）之ModelForm操作、原生Ajax、伪Ajax、文件上传和图片验证码生成

猜你喜欢

转载自blog.csdn.net/Dream_ya/article/details/87081838
今日推荐
TIOBE 5 月榜单：Fortran “复活”进入 Top 10
GCC 14.1 发布
面壁智能发布 Eurux-8x22B 开源大模型 —— 堪称「理科状元」
开源日报 | 谷歌扶持鸿蒙上位；开源Rabbit R1；Docker加持的安卓手机；微软的焦虑和野心；海尔电器把开放平台关了
中国码农的“35岁魔咒”
蘭雅 CorelDRAW 插件 2024.5.1 国际劳动节版，免费下载
Arc Browser for Windows 1.0 正式 GA
90后程序员开发视频搬运软件、不到一年获利超 700 万，结局很刑！
周排行
Java自定义时间格式
同步整形电路
在开发中最最最常用的字符串的属性大集合
Linux 查看端口占用并杀掉
Java基础四：ArrayList
多线程之死锁就是这么简单
mysql 基础命令集
awk 命令详解
Centos6.3编译安装nginx+php步骤
OCR （Optical Character Recognition，光学字符识别）
每日归档
更多
2024-05-08(42)
2024-05-07(14)
2024-05-06(40)
2024-05-05(0)
2024-05-04(7)
2024-05-03(19)
2024-05-02(0)
2024-05-01(4)
2024-04-30(1)
2024-04-29(40)

代码天地 © 2018 codetd.com

境外服务器   最新电视剧2022