【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

"""
Django settings for mainproject project.

Generated by 'django-admin startproject' using Django 2.2.11.

For more information on this file, see
https://docs.djangoproject.com/en/2.2/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/2.2/ref/settings/
"""

import os

# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/2.2/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'ho#q8-%k2zlqb($n&s^=lfa5!de66vb0kimp0k@(8*j8mj^eg^'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

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

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',
]

ROOT_URLCONF = 'mainproject.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(BASE_DIR, 'templates')]
        ,
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'mainproject.wsgi.application'


# Database
# https://docs.djangoproject.com/en/2.2/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}


# Password validation
# https://docs.djangoproject.com/en/2.2/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/2.2/topics/i18n/

LANGUAGE_CODE = 'zh-Hans'

TIME_ZONE = 'Asia/Shanghai'

USE_I18N = True

USE_L10N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/2.2/howto/static-files/

STATIC_URL = '/static/'

　　urls.py

from django.contrib import admin
from django.conf.urls import url
from firstWEB import views
urlpatterns = {
    url('admin/', admin.site.urls),
    url(r'^index/', views.index),
    url(r'^calpage/', views.CalPage),
    url(r'^cal', views.Cal),
    url(r'^list', views.CalList),
    url(r'^del', views.DelData)
}

应用firstWEB

models.py

from django.db import models

# Create your models here.models文件是对表的描述

class cal(models.Model):
    value_a = models.CharField(max_length=10)
    value_b = models.CharField(max_length=10)
    result = models.CharField(max_length=10)

views.py

from __future__ import unicode_literals
from django.shortcuts import render
from django.http import HttpResponse
from firstWEB.models import cal


# Create your views here.

def index(request):
    return render(request, 'index.html')


def CalPage(request):
    return render(request, 'cal.html')


def Cal(request):
    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。
        value_a = request.POST['valueA']
        value_b = request.POST['valueB']
        print(value_a, value_b)
        result = int(value_a) + int(value_b)
        # 把各个字段数据存储到数据库中
        cal.objects.create(value_a=value_a, value_b=value_b, result=result)
        return render(request, 'result.html', context={'data': result})
    else:
        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。

直接访问http://127.0.0.1:8000/cal报错信息现象

def CalList(request):
    data = cal.objects.all()
    # for data in data:
    #    print(data.value_a,data.value_b,data.result)
    return render(request, 'list.html', context={'data': data})


def DelData(request):
    cal.objects.all().delete()
    return HttpResponse('data Deleted')

templates--

index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>My first Web from Django</title>
</head>
<body>
<h1 style="color:red">My first Django website</h1>
</body>
</html>

cal.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>计算页面</title>
</head>
<body>
<form method="POST" action="/cal">
    {% csrf_token %}
    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">
</form>
</body>
</html>

 

 点击提交

result.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>结果页面</title>
</head>
<body>
<h1>计算结果是：</h1><h2>{{ data }}</h2>
</body>
</html>

list.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Cal LIST</title>
</head>
<body>
<table border="1">
    <thead>
    <tr>
        <th>valueA</th><th>valueB</th><th>result</th>
    </tr>
    </thead>

    {% for data in data %}
    <tr>
        <td>{{ data.value_a }}</td><td>{{ data.value_b }}</td><td>{{ data.result }}</td>
    </tr>
{% endfor %}

</table>
<form action="del" method="POST">
    {% csrf_token %}
    <input type="submit" value="清库">
</form>
</body>
</html>

访问：http://127.0.0.1:8000/list

 点击“清库”

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