简单的后台管理

1登录注册
2 老师
 班级
 学员
 insert update delete 

1.设计表结构

# 班级表
class CLASS(models.Model):
  caption = models.CharField(max_length=32)
# 学生表
class STUDENT(models.Model):
  name = models.CharField(max_length=32)
  cls = models.ForeignKey('CLASS',on_delete=models.CASCADE)
# 教师表
class TEACHER(models.Model):
  name = models.CharField(max_length=32)
  stu = models.ManyToManyField('CLASS')
# 后台管理表
class ADMINISTRATOR(models.Model):
  username = models.CharField(max_length=32)
  password = models.CharField(max_length=32)

# 初始化数据表
python manage.py makemigrations	
python manage.py migrate

2.登录

form 表单
ajax 
用户密码正确 
保持会话 
session 
cookie
redirect('/index')
错误 页面提示  <span>用户名或密码错误</span>

3.  	保存在客户端
    	可以主动清除
    	不能跨域
    	保存在浏览器的键值对
   

	import datetime 
	datetime.datetime.utcnow()+datetime.detaltime(10)
	set_cookie   参数 max_age=10,expires=10
	path='/'
	domain=None

4.通过js 操作cookie
jquery.cookie.js

​

​
5.加密的cookie

response.set_signed_cookie("Ab","123456",max_age=10,expires=10,path='/')
			if request.get_signed_cookie('Ab'):

6.session

session 是服务器端的键值对，依赖于cookie机制
session==>key:value 
浏览器中保存cookie 保存了session的key，下次请求携带key来请求	
同一个用户不同浏览器登录是否随机key不一样。在服务端中是否有多条session			
request.session['is_login']=True
if request.session.get('is_login'):
  request.session.create()
  --session是一个字典操作，也可以指定删除 del request.session['is_login'] 

7.装饰器控制uri访问

def auth(fn):
  def inner(request,*args,**kwargs):
    if request.session.get('is_login'):
      return fn(request,*args,**kwargs)
    else:
      return redirect('/login')
  return inner

8.FBV和CBV
chorme的插件postman插件

from django import views
class longin(views.View):
  msg = ""
  def post(self,request, *args, **kwargs):
    u = request.POST.get("user")
	p = request.POST.get("pwd")
	if models.ADMINISTRATOR.objects.filter(username=u, password=p).count():
	  request.session['is_login'] = True
	  return redirect('/index')
    else:
	  self.msg = "用户或密码错误"
	  return render(request,'login.html',{"msg":self.msg})

   def get(self,request, *args, **kwargs):
	 return render(request,'login.html')

​
修改url样式
path('login/', views.longin.as_view())

CBV形式下的装饰器
写法一：

from django.utils.decorators import method_decorator
class index(views.View):
    @method_decorator(auth)
    def get(self,request,*args,**kwargs):
        return render(request,'index.html')

写法二：

class userinfo(views.View):
    def dispatch(self, request, *args, **kwargs):
        if request.session.get('is_login'):
            result=views.View.dispatch(self, request, *args, **kwargs)
            return result
        else:
            return redirect('/login')
    def get(self,request,*args,**kwargs):
        return render(request,'userinfo.html')

写法三：

class userinfo(views.View):
    @method_decorator(auth)
    def dispatch(self, request, *args, **kwargs):
        result=views.View.dispatch(self, request, *args, **kwargs)
        return result
    def get(self,request,*args,**kwargs):
        return render(request,'userinfo.html')

写法四：

@method_decorator(auth,name='dispatch')
class userinfo(views.View):
    def dispatch(self, request, *args, **kwargs):
        result=views.View.dispatch(self, request, *args, **kwargs)
        return result
    def get(self,request,*args,**kwargs):
        return render(request,'userinfo.html')

Django中使用ajax post向后台传送数据时403 Forbidden (CSRF token missing or incorrect.):的解决办法
书写方式一：

{% csrf_token %}
<input type="text" name="username">
<input type="submit" id="aja"></input>
<script src="/static/jquery-3.5.1.js"></script>
<script>$("#aja").on("click",function(){
    $.ajax({url:"/login1/",
            type:"POST",
            data:{AA:123,csrfmiddlewaretoken:$('[name="csrfmiddlewaretoken"]').val()},
            datatype: "JSON",
            success:function(data){
                console.log(data)
            }
           })
})

书写方式二：

<input type="text" name="username">
<input type="submit" id="aja"></input>
<script src="/static/jquery-3.5.1.js"></script>
<script>
    $("#aja").on("click",function(){
    $.ajax({url:"/login1/",
            type:"POST",
            data:{AA:123,csrfmiddlewaretoken:'{{ csrf_token }}'},
            datatype: "JSON",
            success:function(data){
                console.log(data)
            }
           })
})

​