django 第三天 视图

Posted 2020-11-24 xiaobai686

今日内容

一、url路由分发之include

项目文件夹下的urls.py文件中的url写法:
    from django.conf.urls import url,include
    from django.contrib import admin
    from app01 import views
    urlpatterns = [
        # url(r'^admin/', admin.site.urls),
        #首页
        url(r'^$', views.base),

        url(r'^app01/', include('app01.urls')),

        url(r'^app02/', include('app02.urls')),

    ]
    
app01下urls.py内容写法
    from django.conf.urls import url
    from django.contrib import admin
    from app01 import views
    urlpatterns = [
        # url(r'^admin/', admin.site.urls),
        url(r'^$', views.app01base),
        url(r'^index/', views.index),
    ]
    
app02下urls.py内容写法   
    from django.conf.urls import url
    from django.contrib import admin
    from app02 import views

    urlpatterns = [
        # url(r'^admin/', admin.site.urls),
        url(r'^$', views.app02base),
        url(r'^home/', views.home),

    ]

二、视图

1.请求相关的属性方法

• (request--HttpRequest对象)

def index(request): #http相关请求信息---封装--HttpRequest对象

    if request.method == 'GET':
        print(request.body)  #获取post请求提交过来的原始数据
        print(request.GET)   #获取GET请求提交的数据
        # print(request.META)  # 请求头相关信息,就是一个大字典
        print(request.path) #/index/ 路径
        print(request.path_info) #/index/ 路径
        print(request.get_full_path())  #/index/?username=dazhuang&password=123
        
        return render(request,'index.html')
    else:
        print(request.body)  # b'username=dazhuang'
        print(request.POST) #获取POST请求提交的数据
        return HttpResponse('男宾三位,拿好手牌!')

2.响应相关的方法

• HttpResponse --- 回复字符串的时候来使用
• render --- 回复一个html页面的时候使用
• redirect -- 重定向

redirect -- 重定向
    示例:
    def login(request):
        if request.method == 'GET':
            return render(request,'login.html')
        else:
            username = request.POST.get('username')
            password = request.POST.get('password')
            if username == 'taibai' and password == 'dsb':
                # return render(request,'home.html')
                return  redirect('/home/')  #重定向
            else:
                return HttpResponse('滚犊子,赶紧去充钱!!!')
    #首页
    def home(request):
        return render(request,'home.html')

3.FBV和CBV

3.1 FBV

FBV -- function based view
def home(request):
    print('home!!!')
    return render(request,'home.html')

3.2 CBV

• 在视图里使用类处理
• 优点
  • 提高了代码的复用性
  • 用不同的函数针对不同的HTTP方法处理，而不是通过if判断。提高代码的可读性

CBV  -- class based view
views.py
    from django.shortcuts import render,HttpResponse,redirect
    from django.views import View
    class LoginView(View):
        # 通过请求方法找到自己写的视图类里面对应的方法
        def get(self,request):        
            return render(request,'login2.html')
        
        def post(self,request):
            username = request.POST.get('uname')
            password = request.POST.get('pwd')
            print(username,password)
            return HttpResponse('登录成功!')
            
urls.py
    url(r'^login2/', views.LoginView.as_view()),

4.CBV通过不同的请求方法找到对应的试图类中的方法

4.1关键点,反射

    def dispatch(self, request, *args, **kwargs):
        if request.method.lower() in                    self.http_method_names:
        handler = getattr(self, request.method.lower(), self.http_method_not_allowed)  #反射

4.2CBV的dispatch方法

from django.views import View
class LoginView(View):
    # GET 
    def dispatch(self, request, *args, **kwargs):
        print('请求来啦')
        ret = super().dispatch(request, *args, **kwargs)
        print('到点了,走人了')
        return ret
    def get(self,request):
        print('get方法执行了')
        return render(request,'login2.html')
    def post(self,request):
        username = request.POST.get('uname')
        password = request.POST.get('pwd')
        print(username,password)
        return HttpResponse('登录成功!')

4.3FBV加装饰器

def n1(f):
    def n2(*args,**kwargs):
        print('请求之前')
        ret = f(*args,**kwargs)
        print('请求之后')
        return ret
    return n2
@n1
def home(request):
    print('home!!!')
    return render(request,'home.html')

4.4CBV加装饰器

from django.views import View
from django.utils.decorators import method_decorator

def n1(f):
    def n2(*args,**kwargs):
        print('请求之前')
        ret = f(*args,**kwargs)
        print('请求之后')
        return ret
    return n2

# @method_decorator(n1,name='get') #方式三
class LoginView(View):
    # GET
    # @method_decorator(n1)  #方式2 给所有方法加装饰器
    def dispatch(self, request, *args, **kwargs):
        # print('请求来啦')
        ret = super().dispatch(request, *args, **kwargs)
        # print('到点了,走人了')
        return ret

    # @method_decorator(n1)  #方式1
    def get(self,request):
        print('get方法执行了')
        return render(request,'login2.html')
    def post(self,request):
        username = request.POST.get('uname')
        password = request.POST.get('pwd')
        print(username,password)
        return HttpResponse('登录成功!')