AI-CBV写法
CBV固定样式
#url.py from django.conf.urls import url from django.contrib import admin from app01 import views urlpatterns = [ url(r'^admin/', admin.site.urls), url(r'^login/', views.Loginview.as_view()), #CBV格式，Loginview是类名 ]
# views.py from django.shortcuts import render,HttpResponse from django.views import View # Create your views here. class Loginview(View): #里边可以封装很多方法 def get(self,request): return render(request,"login.html",locals()) def post(self,request): return HttpResponse("post")
#login.html <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <link href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.7/css/bootstrap.css" rel="stylesheet"> </head> <body> <form action="" method="post"> {% csrf_token %} 用户名：<input type="text" name="user"> 密码：<input type="password" name="pwd"> <button type="submit">提交</button> </form> </body> </html>
CBV源码解析
#1.从url开始执行 urlpatterns = [ url(r'^admin/', admin.site.urls), url(r'^login/', Views.Loginview.as_view()), #CBV格式，Loginview是类名 ] #2.url(r'^login/', views.Loginview.as_view()) 代表在Loginview继承的View类中找as_view方法 def as_view(cls, **initkwargs): def view(request, *args, **kwargs): self = cls(**initkwargs) if hasattr(self, 'get') and not hasattr(self, 'head'): # self,即Login_View对象 self.head = self.get self.request = request self.args = args self.kwargs = kwargs return self.dispatch(request, *args, **kwargs) return view # 3.调用as_view方法时，返回了view,相当于 url(r'^login/', Views.view) # 4.一旦用户get访问login,相当于给view传参view(request) def view(request, *args, **kwargs): self = cls(**initkwargs) #5.cls为当前类的实例化对象，即LoginView的实例化对象 if hasattr(self, 'get') and not hasattr(self, 'head'): # self,即Login_View对象 self.head = self.get self.request = request self.args = args self.kwargs = kwargs return self.dispatch(request, *args, **kwargs) #6.表示从LoginView的实例化对象中找dispatch方法 # 7.找不到dispatch方法，就在View中找 class Loginview(View): #里边可以封装很多方法 def get(self,request): return render(request,"login.html",locals()) # 8. 找到dispatch方法， class View(object): http_method_names = ['get', 'post', 'put', 'patch', 'delete', 'head', 'options', 'trace'] def dispatch(self, request, *args, **kwargs): if request.method.lower() in self.http_method_names: # handler表示get、post等 handler = getattr(self, request.method.lower(), self.http_method_not_allowed) #8.self不在request.method.lower()中， # 就使用self.http_method_not_allowed进行报错处理 else: handler = self.http_method_not_allowed return handler(request, *args, **kwargs) #9.执行handler(get()、post()等方法) # 10.执行get等方法，返回前端页面，完毕 class Loginview(View): #里边可以封装很多方法 def get(self,request): return render(request,"login.html",locals())
CBV重写dispatch
# views.py from django.shortcuts import render,HttpResponse from django.views import View # Create your views here. class Loginview(View): #里边可以封装很多方法 def dispatch(self, request, *args, **kwargs): print("可以将公共的功能放到此处") #其实这样写，和没有写dispatch方法功能一样，"多此一举"？不是，有用处滴！ # 每次执行代码都会走这个dispatch方法，可以将公共的功能放到此处 ret=super().dispatch(request,*args,**kwargs) #覆盖源码dispatch功能 return ret def get(self,request): return render(request,"login.html",locals()) def post(self,request): return HttpResponse("post")