Python Django 之简单入门

一、下载Django并安装

1、下载Django

2、安装

二、新建Django project

1、使用django-admin新建mysite 项目

django-admin startproject mysite

在C:\Users\hope\python目录新建Django项目

2、查看mysite里面的内容

1）外层mysite

2）内存mysite

settings（设置）、url（路由分配）、wsgi（web服务器）

三、新建APP

1、使用python manage.py startapp 新建app

python manage.py startapp blog

2、查看新建app

3、查看app内的文件

四、简单的Djagno使用一

注意：

1）request接收前端数据

2）HttpResponse的使用，向前端发送数据

1、url

from django.contrib import admin
from django.urls import path
from blog import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('cur_time/',views.cur_time),

2、views

from django.shortcuts import render,HttpResponse

# Create your views here.
def cur_time(request):
    return HttpResponse("<h1>ok</h1>")

3、templates

暂无

4、启动

python manage.py runserver 8080

五、简单的Djagno使用二--后端向前端发送数据

注意：

1）render的使用：render封装了HttpResponse

2）render后端向前端，发送数据的格式render(request,"cur_time.html",{"abc":times})

3）前端接收后端数据格式{{ }}

1、url

from django.contrib import admin
from django.urls import path
from blog import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('cur_time/',views.cur_time),

2、views

from django.shortcuts import render,HttpResponse
import datetime
# Create your views here.
def cur_time(request):
    times=datetime.datetime.now()
    return render(request,"cur_time.html",{"abc":times})

3、templates

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<h1>当前时间:{{ abc }}</h1>
</body>
</html>

4、启动

不用重新启动，Django会自动刷新

六、简单的Djagno使用三--前端向后端发送数据

注意：

1）action

2）method

3）req: req.POST.get

1、url

from django.contrib import admin
from django.urls import path
from blog import views
urlpatterns = [
path('admin/', admin.site.urls),
path('cur_time/',views.cur_time),
path('userInfo/',views.userInfo),
]

2、views

from django.shortcuts import render,HttpResponse
import datetime
# Create your views here.
def userInfo(req):
    if req.method=="POST":
        username=req.POST.get("username",None)
        sex=req.POST.get("sex", None)
        email=req.POST.get("email", None)

        print(username)
        print(sex)
        print(email)
    return render(req,"index.html")

3、templates

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/userInfo/" method="post">
    <p>姓名<input type="text" name="username"></p>
    <p>性别<input type="text" name="sex"></p>
    <p>邮箱<input type="text" name="email"></p>
    <p><input type="submit" name="submit"></p>

</form>
</body>
</html>

4、启动填写提交的信息

5、Forbidden（跨站请求攻击）与处理

1）点击提交，出现Forbidden (403) 跨站请求攻击

2）处理Forbidden (403)

注释掉setting中的MIDDLEWARE的 'django.middleware.csrf.CsrfViewMiddleware',

3）再次点击提交

4）后台输出对应的数据

七、简单的Djagno使用四--前后端数据交互

1、url

from django.contrib import admin
from django.urls import path
from blog import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('cur_time/',views.cur_time),
    path('userInfo/',views.userInfo),
]

2、views

from django.shortcuts import render,HttpResponse
import datetime
# Create your views here.
user_list=[]
def userInfo(req):
    if req.method=="POST":
        username=req.POST.get("username",None)
        sex=req.POST.get("sex", None)
        email=req.POST.get("email", None)

        user={"username":username,"sex":sex,"email":email}
        user_list.append(user)
    return render(req,"index.html",{"user_list":user_list})

3、templates

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/userInfo/" method="post">
    <p>姓名<input type="text" name="username"></p>
    <p>性别<input type="text" name="sex"></p>
    <p>邮箱<input type="text" name="email"></p>
    <p><input type="submit" name="submit"></p>

</form>
<hr>
<h1>
    数据展示
</h1>
<tale border="10px">
    <tr>
            <td>姓名</td>
            <td>性别</td>
            <td>邮箱</td>
    </tr>
    <br/>
    <tr>
        {% for i in user_list %}
            <td>{{ i.username }}</td>
            <td>{{ i.sex }}</td>
            <td>{{ i.email }}</td>
            <br/>
        {% endfor %}
    </tr>

</tale>
</body>
</html>

4、启动展示

1）前台输入新数据到后端

2）前台展示后端发来的数据

八、简单的Djagno使用四--从数据库中存取数据

注意：

1）setting查看数据库配置

2）models写法

1、url

from django.contrib import admin
from django.urls import path
from blog import views
urlpatterns = [
    path('admin/', admin.site.urls),
    #path('cur_time/',views.cur_time),
    path('userInfo/',views.userInfo),
]

2、views

from django.shortcuts import render,HttpResponse
import datetime
from blog import models

def userInfo(req):
    if req.method=="POST":
        u=req.POST.get("username",None)
        s=req.POST.get("sex", None)
        e=req.POST.get("email", None)
        models.UserInfo.objects.create(
            username=u,
            sex=s,
            email=e,
        )
    user_list=models.UserInfo.objects.all()

    return render(req,"index.html",{"user_list":user_list})

3、 templates

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/userInfo/" method="post">
    <p>姓名<input type="text" name="username"></p>
    <p>性别<input type="text" name="sex"></p>
    <p>邮箱<input type="text" name="email"></p>
    <p><input type="submit" name="submit"></p>

</form>
<hr>
<h1>
    数据展示
</h1>
<table border="1px">
    <tr>
            <td>姓名</td>
            <td>性别</td>
            <td>邮箱</td>
    </tr>
    <br/>
    <tr>
        {% for i in user_list %}
            <td>{{ i.username }}</td>
            <td>{{ i.sex }}</td>
            <td>{{ i.email }}</td>

        {% endfor %}
    </tr>
<br/>
</table>
</body>
</html>

4、models

from django.db import models

# Create your models here.
class UserInfo(models.Model):
    username=models.CharField(max_length=60)
    sex = models.CharField(max_length=60)
    email = models.CharField(max_length=60)

5、database

python manage.py makemigrations

python manage.py migrate

6、重启后数据不再丢失