【Python】【Django】通俗易懂Python Django网站开发绝对零入门(1小时入门)第一季

一针见血的学习网址：

https://www.bilibili.com/video/av62405790?from=search&seid=15110123406808421495

Django 框架

关于网站框架的MVC结构

Django框架的MVC

Django框架的MVC流程

Django框架创建流程

Django框架目录的简单介绍

今天需要完成的任务

几个命令入门期间比较重要

命令行创建环境工程及应用

html中form表单

<form method="POST" action="/cal">

　　第一个数字<input type="number" name="valueA">
　　+
　　第二个数字<input type="number" name="valueB">
　　<input type="submit" value="提交计算">//submit点击提交按钮后页面会跳转到url对应名字为/cal中，会进入对应方法views.Cal中

用Pycharm中自带的数据库Sqlite

Download相关未下载内容，到当前项目中选择dbsqlite3文件，test测试连接是否可以跑通，successful 后进行数据库迁移操作：

1.创建迁移

(venv) F:scriptpy_scriptsmainproject>python manage.py makemigrations

2.执行迁移操作

(venv) F:scriptpy_scriptsmainproject>python manage.py migrate

刷新右侧数据库，关注“FirstWEB”表及其中字段

一个易错点

-----------------------------------------------------------------------------------------------------------------------------------------------------------

代码具体内容：

代码台式机路径：

mainproject

　　settings.py

  1 """
  2 Django settings for mainproject project.
  3 
  4 Generated by 'django-admin startproject' using Django 2.2.11.
  5 
  6 For more information on this file, see
  7 https://docs.djangoproject.com/en/2.2/topics/settings/
  8 
  9 For the full list of settings and their values, see
 10 https://docs.djangoproject.com/en/2.2/ref/settings/
 11 """
 12 
 13 import os
 14 
 15 # Build paths inside the project like this: os.path.join(BASE_DIR, ...)
 16 BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 17 
 18 
 19 # Quick-start development settings - unsuitable for production
 20 # See https://docs.djangoproject.com/en/2.2/howto/deployment/checklist/
 21 
 22 # SECURITY WARNING: keep the secret key used in production secret!
 23 SECRET_KEY = 'ho#q8-%k2zlqb($n&s^=lfa5!de66vb0kimp0k@(8*j8mj^eg^'
 24 
 25 # SECURITY WARNING: don't run with debug turned on in production!
 26 DEBUG = True
 27 
 28 ALLOWED_HOSTS = []
 29 
 30 
 31 # Application definition
 32 
 33 INSTALLED_APPS = [
 34     'django.contrib.admin',
 35     'django.contrib.auth',
 36     'django.contrib.contenttypes',
 37     'django.contrib.sessions',
 38     'django.contrib.messages',
 39     'django.contrib.staticfiles',
 40     'firstWEB',
 41 ]
 42 
 43 MIDDLEWARE = [
 44     'django.middleware.security.SecurityMiddleware',
 45     'django.contrib.sessions.middleware.SessionMiddleware',
 46     'django.middleware.common.CommonMiddleware',
 47     'django.middleware.csrf.CsrfViewMiddleware',
 48     'django.contrib.auth.middleware.AuthenticationMiddleware',
 49     'django.contrib.messages.middleware.MessageMiddleware',
 50     'django.middleware.clickjacking.XFrameOptionsMiddleware',
 51 ]
 52 
 53 ROOT_URLCONF = 'mainproject.urls'
 54 
 55 TEMPLATES = [
 56     {
 57         'BACKEND': 'django.template.backends.django.DjangoTemplates',
 58         'DIRS': [os.path.join(BASE_DIR, 'templates')]
 59         ,
 60         'APP_DIRS': True,
 61         'OPTIONS': {
 62             'context_processors': [
 63                 'django.template.context_processors.debug',
 64                 'django.template.context_processors.request',
 65                 'django.contrib.auth.context_processors.auth',
 66                 'django.contrib.messages.context_processors.messages',
 67             ],
 68         },
 69     },
 70 ]
 71 
 72 WSGI_APPLICATION = 'mainproject.wsgi.application'
 73 
 74 
 75 # Database
 76 # https://docs.djangoproject.com/en/2.2/ref/settings/#databases
 77 
 78 DATABASES = {
 79     'default': {
 80         'ENGINE': 'django.db.backends.sqlite3',
 81         'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
 82     }
 83 }
 84 
 85 
 86 # Password validation
 87 # https://docs.djangoproject.com/en/2.2/ref/settings/#auth-password-validators
 88 
 89 AUTH_PASSWORD_VALIDATORS = [
 90     {
 91         'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
 92     },
 93     {
 94         'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
 95     },
 96     {
 97         'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
 98     },
 99     {
100         'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
101     },
102 ]
103 
104 
105 # Internationalization
106 # https://docs.djangoproject.com/en/2.2/topics/i18n/
107 
108 LANGUAGE_CODE = 'zh-Hans'
109 
110 TIME_ZONE = 'Asia/Shanghai'
111 
112 USE_I18N = True
113 
114 USE_L10N = True
115 
116 USE_TZ = True
117 
118 
119 # Static files (CSS, JavaScript, Images)
120 # https://docs.djangoproject.com/en/2.2/howto/static-files/
121 
122 STATIC_URL = '/static/'

　　urls.py

 1 from django.contrib import admin
 2 from django.conf.urls import url
 3 from firstWEB import views
 4 urlpatterns = {
 5     url('admin/', admin.site.urls),
 6     url(r'^index/', views.index),
 7     url(r'^calpage/', views.CalPage),
 8     url(r'^cal', views.Cal),
 9     url(r'^list', views.CalList),
10     url(r'^del', views.DelData)
11 }

View Code

应用firstWEB

models.py

1 from django.db import models
2 
3 # Create your models here.models文件是对表的描述
4 
5 class cal(models.Model):
6     value_a = models.CharField(max_length=10)
7     value_b = models.CharField(max_length=10)
8     result = models.CharField(max_length=10)

views.py

 1 from __future__ import unicode_literals
 2 from django.shortcuts import render
 3 from django.http import HttpResponse
 4 from firstWEB.models import cal
 5 
 6 
 7 # Create your views here.
 8 
 9 def index(request):
10     return render(request, 'index.html')
11 
12 
13 def CalPage(request):
14     return render(request, 'cal.html')
15 
16 
17 def Cal(request):
18     if request.POST:#如果是post访问才进入，避免如果本来是post才能访问到的html网址，通过get url链接访问会报错。
19         value_a = request.POST['valueA']
20         value_b = request.POST['valueB']
21         print(value_a, value_b)
22         result = int(value_a) + int(value_b)
23         # 把各个字段数据存储到数据库中
24         cal.objects.create(value_a=value_a, value_b=value_b, result=result)
25         return render(request, 'result.html', context={'data': result})
26     else:
27         return HttpResponse('Please visit us with POST')#如果非post方式访问（可能是直接输入链接进行访问。如果是post访问时上一个页面post方式提交信息到此html页面的方式），报错。
28 
直接访问http://127.0.0.1:8000/cal报错信息现象

29 def CalList(request):
30     data = cal.objects.all()
31     # for data in data:
32     #    print(data.value_a,data.value_b,data.result)
33     return render(request, 'list.html', context={'data': data})
34 
35 
36 def DelData(request):
37     cal.objects.all().delete()
38     return HttpResponse('data Deleted')

templates--

index.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>My first Web from Django</title>
 6 </head>
 7 <body>
 8 <h1 style="color:red">My first Django website</h1>
 9 </body>
10 </html>

cal.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>计算页面</title>
 6 </head>
 7 <body>
 8 <form method="POST" action="/cal">
 9     {% csrf_token %}
10     第一个数字<input type="number" name="valueA">
11     +
12     第二个数字<input type="number" name="valueB">
13     <input type="submit" value="提交计算">
14 </form>
15 </body>
16 </html>

点击提交

result.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>结果页面</title>
 6 </head>
 7 <body>
 8 <h1>计算结果是：</h1><h2>{{ data }}</h2>
 9 </body>
10 </html>

list.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>Cal LIST</title>
 6 </head>
 7 <body>
 8 <table border="1">
 9     <thead>
10     <tr>
11         <th>valueA</th><th>valueB</th><th>result</th>
12     </tr>
13     </thead>
14 
15     {% for data in data %}
16     <tr>
17         <td>{{ data.value_a }}</td><td>{{ data.value_b }}</td><td>{{ data.result }}</td>
18     </tr>
19 {% endfor %}
20 
21 </table>
22 <form action="del" method="POST">
23     {% csrf_token %}
24     <input type="submit" value="清库">
25 </form>
26 </body>
27 </html>

访问：http://127.0.0.1:8000/list

点击“清库”

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