python框架之Django(4)-视图&路由

视图

负责接收请求和返回响应

FBV和CBV

FBV

FBV（function base views）就是在视图里使用函数处理请求。

 from django.conf.urls import url

 from django.contrib import admin

 from test_app import views

 urlpatterns = [

     url(r'^test/', views.test),

 ]

/[project name]/urls.py

 from django.shortcuts import render

 def test(request):

     if (request.method == 'POST'):

         ...  # do something

     else:

         ...  # do something

/[app name]/views.py

CBV

CBV（class base views）就是在视图里使用类处理请求。

 from django.conf.urls import url

 from django.contrib import admin

 from test_app import views

 urlpatterns = [

     url(r'^test/', views.Test.as_view()),

 ]

/[project name]/urls.py

 from django.shortcuts import render

 from django.views import View

 class Test(View):

     def get(self, request):

         ... # do something

     def post(self, request):

         ... # do something

/[app name]/views.py

request

1. request.method    # 获取请求的方法（GET、POST等）

2. request.GET       # 通常用来获取URL里面的参数

3. request.POST      # 用来获取POST提交过来的数据

4. request.path_info # 获取用户请求的路径(不包含IP和端口和URL参数)

5. request.body      # 获取请求正文

response

1. HttpResponse        # 返回字符串内容

2. render              # 渲染并返回html页面

3. redirect            # 返回一个重定向

4. JsonResponse        # 将对象序列化成Json格式字符串并返回

路由

格式

from django.conf.urls import url

urlpatterns = [

     url([正则], [视图函数]，[参数]，name=[别名]),

]

# 注意:Django 2.0中有所不同,如下:

from django.urls import path

urlpatterns = [

    path([正则], [视图函数]，[参数]，name=[别名]),

]

分组匹配

位置匹配

 from django.conf.urls import url

 from test_app import views

 urlpatterns = [

     url(r'^test/([a-zA-z]+)/([0-9]{1,2})', views.Test.as_view()),

 ]

/[project name]/urls.py

 from django.shortcuts import render, HttpResponse

 from django.views import View

 class Test(View):

     def get(self, request, name, age):

         resp_str = '姓名:{} 年龄:{}'.format(name,age)

         return HttpResponse(resp_str)

/[app name]/views.py

result

命名匹配

 from django.conf.urls import url

 from test_app import views

 urlpatterns = [

     url(r'^test/(?P<name>[a-zA-z]+)/(?P<age>[0-9]{1,2})/', views.Test.as_view()),

 ]

/[project name]/urls.py

 from django.shortcuts import render, HttpResponse

 from django.views import View

 class Test(View):

     def get(self, request, age, name):

         resp_str = '姓名:{} 年龄:{}'.format(name,age)

         return HttpResponse(resp_str)

/[app name]/views.py

result

include

可以让路由信息保存在多个文件中

 from django.conf.urls import url,include

 urlpatterns = [

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

 ]

/[project name]/urls.py

 from django.conf.urls import url, include

 from . import views

 urlpatterns = [

     url(r'^test', views.Test.as_view())

 ]

/[app name]/urls.py

上述配置对应的地址就是： http://localhost:8000/test_app/test

URL命名&反向解析

 from django.conf.urls import url

 from test_app import views

 urlpatterns = [

     url(r'^test/([a-zA-Z]+)/([0-9]{1,2})', views.Test.as_view(), name='test_name')

 ]

/[project name]/urls.py

 from django.shortcuts import render

 from django.views import View

 from django.urls import reverse

 class Test(View):

     def get(self, request, name, age):

         request_url = reverse('test_name',args=(name,age))

         reverse_url = reverse('test_name',args=('zhangsan',20))

         return render(request, 'test.html', {'request_url':request_url,'reverse_url': reverse_url})

/[app name]/views.py

 <!DOCTYPE html>

 <html lang="en">

 <head>

     <meta charset="UTF-8">

     <title>test</title>

 </head>

 <body>

 请求的URL:

 <br>

 {{ request_url }}

 <hr>

 视图中解析：<br>

 {{ reverse_url }}

 <hr>

 模板中解析：<br>

 {% url 'test_name' 'zhangsan' 19 %}

 </body>

 </html>

/templates/test.html

result

补充

APPEND_SLASH

settings.py配置文件中默认没有 APPEND_SLASH这个项，但Django默认这个参数为 APPEND_SLASH = True。作用就是自动在网址结尾加'/'。（测试不生效注意清理历史缓存）

给视图传递额外参数

 from django.conf.urls import url

 from test_app import views

 urlpatterns = [

     url(r'^test/([a-zA-Z]+)/([0-9]{1,2})', views.Test.as_view(), {'sex': 'male'})

 ]

/[project name]/urls.py

 from django.shortcuts import render, HttpResponse

 from django.views import View

 class Test(View):

     def get(self, request, age, name,sex):

         resp_str = '姓名:{} 年龄:{} 性别:{}'.format(name,age,sex)

         return HttpResponse(resp_str)

/[app name]/views.py

result

路由中的namespace

用于区分多个app中name相同的url

 from django.conf.urls import url, include

 from test_app import views

 urlpatterns = [

     url(r'^test/',views.Test.as_view()),

     url(r'^test_app1/', include('test_app1.urls', namespace='app1')),

     url(r'^test_app2/', include('test_app2.urls', namespace='app2')),

 ]

/django_test/urls.py

 from django.shortcuts import render

 from django.views import View

 from django.urls import reverse

 class Test(View):

     def get(self, request):

         app1_url = reverse('app1:same_name', args=('zhangsan', 19))

         app2_url = reverse('app2:same_name', args=('lisi', 20))

         return render(request, 'test.html', {'app1_url': app1_url, 'app2_url': app2_url})

/test_app/views.py

 from django.conf.urls import url, include

 from . import views

 urlpatterns = [

     url(r'^test/([a-zA-Z]+)/([0-9]{1,2})', views.Test.as_view(), name='same_name')

 ]

/test_app1/urls.py

 from django.conf.urls import url, include

 from . import views

 urlpatterns = [

     url(r'^test/([a-zA-Z]+)/([0-9]{1,2})', views.Test.as_view(), name='same_name')

 ]

/test_app2/urls.py

 <!DOCTYPE html>

 <html lang="en">

 <head>

     <meta charset="UTF-8">

     <title>test</title>

 </head>

 <body>

 视图中使用

 <br>

 {{ app1_url }}

 <br>

 {{ app2_url }}

 <hr>

 模板中使用

 <br>

 {% url 'app1:same_name' 'zhangsan' 19%}

 <br>

 {% url 'app2:same_name' 'lisi' 20 %}

 </body>

 </html>

/templates/test.html

result

路由分发

路由可以以以下格式多级分发：

 from django.conf.urls import url

 from img_upload import views

 urlpatterns = [

     url(r'^user/', [(

         url(r'^add/', views.add),  # host:port/user/add/

         url(r'^list/', views.list)  # host:port/user/list/

     ), None, None]),

 ]

/django_test/urls.py