“Django之使用SQLite数据库”的版本间的差异

2019年2月10日 (日) 07:18的最新版本

初学者暂时不用理会其中的概念，一步一步照着做即可，出来效果之后再慢慢体会，有问题可以文末留言。

安装和升级django

执行命令，安装扩展库django，如果已安装，尝试升级到最新版

C:\Users\thinkpad\AppData\Local\Programs\Python\Python37\Scripts>pip3 install django
Requirement already satisfied: django in c:\users\thinkpad\appdata\local\programs\python\python37\lib\site-packages
Requirement already satisfied: pytz in c:\users\thinkpad\appdata\local\programs\python\python37\lib\site-packages (from django)
You are using pip version 9.0.1, however version 18.1 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' command.

C:\Users\thinkpad\AppData\Local\Programs\Python\Python37\Scripts>pip3 install django --upgrade
Requirement already up-to-date: django in c:\users\thinkpad\appdata\local\programs\python\python37\lib\site-packages
Requirement already up-to-date: pytz in c:\users\thinkpad\appdata\local\programs\python\python37\lib\site-packages (from django)

创建项目和应用

执行命令，创建网站项目onLinePythonLearning和一个应用questions

D:\teaching\python\实训>django-admin startproject onLinePythonLearning

D:\teaching\python\实训>cd onLinePythonLearning

D:\teaching\python\实训\onLinePythonLearning>python manage.py startapp questions

配置应用

打开网站项目文件夹中的settings.py文件，配置上面创建的应用

INSTALLED_APPS = [
    'questions2',
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
]

创建模型

打开应用questions2文件夹中的models.py文件，增加一个模型

from django.db import models

# Create your models here.

class Question2(models.Model):
    id = models.AutoField(primary_key=True)
    questionContent = models.CharField(max_length=200,unique=True)
    option_a = models.CharField(max_length=50)
    option_b = models.CharField(max_length=50)
    option_c = models.CharField(max_length=50)
    option_d = models.CharField(max_length=50)
    answer = models.CharField(max_length=50)

创建数据表

执行命令，创建数据表

makemigrations会在当前目录下生成一个migrations文件夹，该文件夹的内容就是数据库要执行的内容

D:\teaching\python\实训\onLinePythonLearning>python manage.py makemigrations questions2
Migrations for 'questions2':
  questions2\migrations\0001_initial.py
    - Create model Question2

migrate就是执行之前生成的migrations文件，这一步才是操作数据库的一步

D:\teaching\python\实训\onLinePythonLearning>python manage.py migrate
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, questions2, sessions
Running migrations:
  Applying contenttypes.0001_initial... OK
  Applying auth.0001_initial... OK
...

注册数据表

打开应用questions2的admin.py，注册上面创建的数据表

from django.contrib import admin

# Register your models here.
from .models import Question2
admin.site.register(Question2)

创建超级用户

执行命令，创建超级用户

D:\teaching\python\实训\onLinePythonLearning>python manage.py createsuperuser
Username (leave blank to use 'thinkpad'): admin
Email address: maxin@qq.com
Password:000000
Password (again):000000
This password is too short. It must contain at least 8 characters.
This password is too common.
This password is entirely numeric.
Bypass password validation and create user anyway? [y/N]: y
Superuser created successfully.

启动网站

执行命令，启动网站

D:\teaching\python\实训\onLinePythonLearning>python manage.py runserver
Performing system checks...

System check identified no issues (0 silenced).
January 27, 2019 - 09:21:57
Django version 2.1.5, using settings 'onLinePythonLearning.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CTRL-BREAK.

登陆管理账号

打开浏览器，输入网址http://127.0.0.1:8000/admin/，输入用户名和密码，登录

增加记录

单击question后面的Add，增加几条记录

创建视图

打开应用questions2的views.py文件，创建视图

from django.shortcuts import render
from django.http import HttpResponse
from .models import Question2

# Create your views here.
def index(request):
    htmlCode ='<table border="1px">'
    for row in Question2.objects.all():
        htmlCode +=('<tr><td>'+str(row.id)+'</td><td>'+
                    row.questionContent+'</td><td>A. '+
                    row.option_a+'</td><td>B. '+
                    row.option_b+'</td><td>C. '+
                    row.option_c+'</td><td>D. '+
                    row.option_d+'</td>')
    htmlCode +='</table>'
    return HttpResponse(htmlCode)

配置路由

在应用questions2中新建urls.py文件，配置路由

from django.urls import path
from . import views

urlpatterns = [
        path('',views.index),
        ]

打开网站项目的urls.py文件，配置路由：

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

urlpatterns = [
    path('admin/', admin.site.urls),
    path('check/', include('questions2.urls'))
]

登陆网站，查看数据

在浏览器中输入网址http://127.0.0.1:8000/check/，查看数据库中的数据

参考文档：https://mp.weixin.qq.com/s?__biz=MzI4MzM2MDgyMQ==&mid=2247487707&idx=1&sn=6d8e2e31e8e19e5de2f94257d69e34a5&chksm=eb8abb81dcfd32977652ed1a33104969beb31ff92b69ee88801c23d051b87aa29997ce2c11e7&scene=21#wechat_redirect