Diango路由映射FBV和CBV

django中请求处理方式有2种：FBV（function base views） 和 CBV（class base views）,换言之就是一种用函数处理请求，一种用类处理请求。

FBV

# url.py
from django.conf.urls import url, include
from mytest import views
 
urlpatterns = [
    url(r‘^index/‘, views.index),
]

# views.py
from django.shortcuts import render
 
 
def index(req):
    if req.method == ‘POST‘:
        print(‘method is :‘ + req.method)
    elif req.method == ‘GET‘:
        print(‘method is :‘ + req.method)
    return render(req, ‘index.html‘)

CBV

# urls.py
from mytest import views
 
urlpatterns = [
    # url(r‘^index/‘, views.index),
    url(r‘^index/‘, views.Index.as_view()),
]

# views.py
from django.views import View

 
class Index(View):
    def get(self, req):
        print(‘method is :‘ + req.method)
        return render(req, ‘index.html‘)
 
    def post(self, req):
        print(‘method is :‘ + req.method)
        return render(req, ‘index.html‘)

# 注：类要继承 View ，类中函数名必须小写。

# cbv 模式下继承了django的view类
# 在请求来临的时候，会调用继承类的 dispatch 方法
# 通过反射的方法它会去调用自己写的视图函数, 那么这便是一个切入点，可以在自己的 cbv 视图中，重写这个方法。 
class View(object):

    def dispatch(self, request, *args, **kwargs):
        # Try to dispatch to the right method; if a method doesn't exist,
        # defer to the error handler. Also defer to the error handler if the
        # request method isn't on the approved list.
        if request.method.lower() in self.http_method_names:
            handler = getattr(self, request.method.lower(), self.http_method_not_allowed)
        else:
            handler = self.http_method_not_allowed
        return handler(request, *args, **kwargs)