reference
https://www.bilibili.com/video/BV1NL41157ph
Get started quickly
create project
django-admin startproject 项目名称
Introduction to Default Project Files
mysite/
-manage.py 【项目的管理、启动项目、创建app、数据管理】【不要动】
-mysite/
--__init__.py
--settings.py 【项目配置】【常常操作】
--urls.py 【URL和函数对应关系】【常常操作】
--asgi.py 【接收网络请求】【不要动】
--wsgi.py 【接收网络请求】【不要动】
Run the project:python manage.py runserver
Create APP
python manage.py startapp 应用名称
Introduction to default application files
mysite/
-app01/
--__init__.py
--admin.py 【固定，不用动】django默认提供的admin后台管理
--apps.py 【固定，不用动】app启动类
--migrations/ 【固定，不用动】数据库变更记录
---__init__.py
--models.py 【重要】对数据库操作
--tests.py 【固定，不用动】单元测试
--views.py 【重要】函数
- Register APP, mysite/setting.py
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'app01.apps.App01Config', # 注册APP
]
- Write the corresponding relationship between URL and view function, mysite/urls.py
from app01 import views
urlpatterns = [
path('index/', views.index),
]
- Write the view function, app01/views.py
from django.shortcuts import render,HttpResponse
def index(request):
return HttpResponse("欢迎")
- The templates template corresponds to the view function, app01/templates
def user_list(request):
# 去app目录下的templates目录寻找user_list.html（根据app的注册顺序，逐一去他们的templates中找）
return render(request,"user_list.html")
- Static files, app01/static
{% load static%}
<!DOCTYPE html>
<head>
<title>Document</title>
<link rel="stylesheet" href="{% static 'plugins/bootstrap-3.4.1-dist/css/bootstrap.css' %}">
</head>
<body>
<script src="{% static 'js/jquery.slim.min.js' %}"></script>
<script src="{% static 'plugins/bootstrap-3.4.1-dist/js/bootstrap.js' %}"></script>
</body>
</html>
template syntax
- the code
# views.py
def tpl(request):
name = '张三'
roles = ['管理员', 'CEO', '保安']
user_info = {"name": 'lisi', "salary": 10000, "role": "CEO"}
data_list = [
{"name": 'zhangsan', "salary": 5000, "role": "管理员"},
{"name": 'lisi', "salary": 6000, "role": "CEO"},
{"name": 'wangwu', "salary": 7000, "role": "保安"}
]
return render(request, 'tpl.html', {"n1": name, "n2": roles, "n3": user_info, "n4": data_list})
<!DOCTYPE html>
<html lang="en">
<body>
<h1>模版语法学习</h1>
<div>n1为单个元素:{
{ n1 }}</div>
<hr />
<div>n2为list:{
{ n2 }}</div>
<div>使用.0123代表下标{
{ n2[0] }}</div>
<div>{
{ n2[1] }}</div>
<div>{
{ n2[2] }}</div>
<div>
{% for item in n2 %}
<span>list循环展示{
{ item }}</span>
{% endfor %}
</div>
<hr />
<div>n3为字典:{
{ n3 }}</div>
<div>{
{ n3.name }}</div>
<div>{
{ n3.salary }}</div>
<div>{
{ n3.role }}</div>
{% for k, v in n3.items %}
<div>字典循环{
{ k }} = {
{ v }}</div>
{% endfor %}
<hr />
<div>n4为列表,元素为字典:{
{ n4 }}</div>
<div>{
{ n4[1] }}</div>
<div>{
{ n4[1].name }}</div>
{% for item in n4 %}
<div>{
{ item.name }}</div>
{% endfor %}
{% if n1 == '张三' %}
<h1>aaaa</h1>
{% else %}
<h1>bbbb</h1>
{% endif %}
</body>
</html>
Inside the render of the view function
- Read HTML files with template syntax
- Render internally (template syntax execution and replace data) to get a string containing only HTML tags
- Return the rendered string to the user's browser
request and response
# views.py
def something(request):
# request是一个对象，封装了用户发送过来的所有请求相关数据
# 1、【请求】获取请求方式 GET/POST
print(request.method)
# 2、【请求】在URL上传递值
print(request.GET)
# 3、【请求】通过请求体中提交数据
print(request.POST)
# 4、【响应】HttpResponse("返回内容")，字符串内容返回给请求者
return HttpResponse("返回")
# 5、【响应】读取HTML的内容+渲染 》》字符串，返回给用户浏览器
# return render(request,"something.html",{"title":"title"})
# 6、【响应】让浏览器重定向到其他页面
# return redirect("https://www.baidu.com")
POST request error: CSRF verification failed. Request aborted.
Add in the form form {% csrf_token %}, randomly generated verification mechanism
<!DOCTYPE html>
<html lang="en">
<body>
<form action="/login/" method="post">
{% csrf_token %}
<input type="text" name="user" placeholder="用户名">
<input type="password" name="pwd" placeholder="密码">
<input type="submit" value="提交">
</form>
</body>
</html>
def login(request):
if request.method== "GET":
return render(request,"login.html")
else:
# <QueryDict: {'csrfmiddlewaretoken': ['49xkDn1H448ehzVqKezwcK3x64Z3Py3d0eq
# lBqfIpTIQ6GLtmblEJ8QXza2iMYbf'], 'user': ['zhangsan'], 'pwd': ['123']}>
print(request.POST)
return HttpResponse("登录成功")
database operation
- MySQL database + pymysql, too cumbersome
import pymysql
# 1.连接MySQL
conn = pymysql.connect(host="127.0.0.1",post=3306,user='root',passwd="root123",charset="utf8",db="unicom")
cursor=conn.cursor(cursor=pymysql.cursors.DictCursor)
# 2.发送指令
cursor.execute("insert into admin(username,password,mobile) values('zhangsan','123','15000000000')")
conn.commit()
# 3.关闭连接
cursor.close()
conn.close()
Django is easier to operate the database. It provides an ORM framework internally, and ORM translates the code into SQL statements.
Install third-party modules
conda install mysqlclient
ORM
An ORM can do two things:
- Create, modify, and delete tables in the database (without writing SQL statements) [Unable to create a database, create it yourself]
- Operate the data in the table (without writing SQL statements)
Create your own database
-
Start the Mysql service
mysql -u root -p root123456 -
create database
testcreate database test default charset utf8 collate utf8_general_ci;
Django connects to the database
Configure and modify in mysite/settings.py
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'test', #数据库的名字
'HOST': '127.0.0.1', #数据库地址
'PORT': '3306', #端口
'USER': 'root', #用户名
"PASSWORD": 'root123456', #密码
}
}
django-action-sheet
Create, modify, delete tables in app01/models.py
from django.db import models
class UserInfo(models.Model):
name=models.CharField(max_length=32)
password=models.CharField(max_length=64)
age=models.IntegerField()
'''相当于
create table
app01_userinfo(
id bigint auto_increment primary key,
name varchar(32),
password varchar(64),
age int
)
'''
Command line execution:
python manage.py makemigrations
python manage.py migrate
Notice:
-
APP needs to be registered in setting.py in advance
-
When adding a new column in a table, since there may already be data in the existing column, the new column must specify the data corresponding to the new column
-
set default
age = models.IntegerField(default=2) -
Allow empty
data = models.IntegerField(null=True,blank=True)
-
-
If you want to adjust the table structure during development, just operate the class in models.py, and then execute
python manage.py makemigrationspython manage.py migrate
Data in the operation table
#views.py
from app01.models import Department
def orm(request):
# 1、新建数据
Department.objects.create(title="销售部")
Department.objects.create(title="运营部")
Department.objects.create(title="IT部")
# 2、删除数据
Department.objects.filter(id=1).delete() # 删除符合条件的数据
Department.objects.all().delete() # 删除全部数据
# 3、获取数据
# data_list=[行对象,行对象,...] QuerySet类型
data_list=Department.objects.all() # 获取全部数据
data_list = Department.objects.filter(title="运营部") # 获取所有符合条件的数据
for obj in data_list:
print(obj.id,obj.title)
data = Department.objects.filter(title="运营部").first() # 获取符合条件的第一条数据
# 4、更新数据
Department.objects.all().update(title="IT部") # 更新所有数据
Department.objects.filter(id=3).update(title="IT部") # 更新符合条件的数据
return HttpResponse("成功")
case, user management
1. Display user list
- urls.py
urlpatterns = [
# 案例 用户管理
path('infolist/',views.infolist),
]
- views.py
- Get all user information
- HTML rendering
#views.py
from app01.models import Department,UserInfo
def infolist(request):
# 1、获取数据库中所有的用户信息
data_list=UserInfo.objects.all()
# 2、渲染，返回给用户
return render(request,"infolist.html",{"data_list":data_list})
- templates/infolist.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<table>
<thead>
<tr>
<th>id</th>
<th>姓名</th>
<th>密码</th>
<th>年龄</th>
</tr>
</thead>
<tbody>
{% for item in data_list %}
<tr>
<td>{
{item.id}}</td>
<td>{
{item.name}}</td>
<td>{
{item.password}}</td>
<td>{
{item.age}}</td>
</tr>
{% endfor %}
</tbody>
</table>
</body>
</html>
2. Add users
- urls.py
urlpatterns = [
# 案例用户管理
path('infolist/',views.infolist),
path('infoadd/',views.infoadd),
]
- views.py
- GET, see the page, enter content
- POST, write to the database
def infoadd(request):
# GET，看到页面，输入内容
if request.method=="GET":
return render(request,"infoadd.html")
# POST，写入到数据库
user=request.POST.get("name")
pwd=request.POST.get("pwd")
age=request.POST.get("age")
#添加到数据库
UserInfo.objects.create(name=user,password=pwd,age=age)
return redirect("/infolist/")
- templates/infoadd.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<!--不写action，默认是给当前地址提交post-->
<form method="post">
{% csrf_token %}
<input type="text" name="name" placeholder="用户名">
<input type="password" name="pwd" placeholder="密码">
<input type="text" name="age" placeholder="年龄">
<input type="submit" value="提交">
</form>
</body>
</html>
3. Delete user
- urls.py
urlpatterns = [
# 案例用户管理
path('infolist/',views.infolist),
path('infoadd/',views.infoadd),
path('infodelete/',views.infodelete),
]
- views.py
def infodelete(request):
nid=request.GET.get('nid')
UserInfo.objects.filter(id=nid).delete()
return redirect('/infolist/')
- templates/infolist.html
<tbody>
{% for item in data_list %}
<tr>
<td>{
{item.id}}</td>
<td>{
{item.name}}</td>
<td>{
{item.password}}</td>
<td>{
{item.age}}</td>
<td><a href="/infodelete/?nid={
{item.id}}">删除</a></td>
</tr>
{% endfor %}
</tbody>