django 创建项目运行项目

创建project

https://www.runoob.com/django/django-first-app.html

# 创建project
 django-admin startproject diango1
#创建app
 cd .\diango1\
 django-admin startapp app1
#运行
python manage.py runserver 0.0.0.0:8000

image.png

创建app

在app1 下新建 urls 文件 \diango1\app1\urls.py

from django.contrib import admin
from django.urls import path

from app1.views import hello

urlpatterns = [
    path('app1/', hello),
]

修改 app1/views.py 的内容

from django.http import HttpResponse


def hello(request):
    return HttpResponse("Hello world ! ")

修改 diango1/urls.py 添加path('app1/', include('app1.urls')),

from django.contrib import admin
from django.urls import path, include

urlpatterns = [
    path('admin/', admin.site.urls),
    path('app1/', include('app1.urls')),
]

修改 diango1/settings.py

# INSTALLED_APPS=[] 数组内添加 'app1'
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'app1'
]

浏览器输入
http://127.0.0.1:8000/app1/app1/
即可看到hello world

Django administration

创建项目时在其urlpatterns 已包含admin

urlpatterns = [
    path('admin/', admin.site.urls),
  ]

默认使用sqllite3配置可查看 diango1/settings.py 中DATABASES 配置

python manage.py makemigrations 
python manage.py migrate   #sqlite表中生成 表结构  db.sqlite3
python manage.py createsuperuser  #创建个用户

浏览器输入
http://127.0.0.1:8000/admin

将普通model由admin管理


from django.db import models

# Create your models here.  app1/models.py
class CodeModel(models.Model): 
    name = models.CharField(max_length=50)  # 名字最长为 50 个字符
    code = models.TextField()  # 这个字段没有文本长度的限制

    def __str__(self):
        return 'Code(name={},id={})'.format(self.name,self.id)

from django.contrib import admin

# Register your models here.  app1/admin.py
from django.contrib import admin
from .models import CodeModel

@admin.register(CodeModel)  #重要添加的 交由admin
class CodeModelAdmin(admin.ModelAdmin):
    pass

image.png

中间键

from django.utils.deprecation import MiddlewareMixin
# from django.http import HttpResponse
from django.shortcuts import HttpResponse, redirect


# 方式一：
class MyMiddleware(MiddlewareMixin):
    def process_request(self, request):
        print("process_request",request)
        pass

    def process_view(self, request, view_func, view_args, view_kwargs):
        print("process_view")
        pass

    def process_exception(self, request, exception):
        pass

    def process_response(self, request, response):
        print("process_request",request,response)
        return response

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
    'app1.middlewares.MyMiddleware'
]

2.1 init方法要调用父类方法
init方法在启动服务的时候执行一次

2.2 process_request(self,request)
请求进入中间件后，第一个执行的方法
返回值有两个：Response|None
返回Response，不会再执行视图函数，而是调到process_response方法（此处有坑，最后说）
返回None，或者不return，继续运行
2.3 process_view(self,request,func,args,*kwargs)
运行完process_request后，就运行这个
func是要执行的视图函数，所以：response = func(request) return response，可以得到视图函数的结果
如果调用了func(request)方法，如果不return response的话，视图函数还会执行一次，所以要不就不调用，调用就return
如果手动调用了func(request)方法，视图函数中的异常不会被process_exception(self,request,exception)接收
2.4 process_response(self,request,response)
每次返回response的时候必经的方法
必须return 一个 response，否则页面显示啥？

https://blog.csdn.net/kzl_knight/article/details/90692758