DjangoMTV学习1

Django简介
Pytharm搭建Django项目
Django配置简介
通用视图体验

Django简介

Django的MTV模式MTV分别代表：

   Model(模型)：数据存取层，实现数据持久化Template(模版)：表现层，负责如何把页面展示给用户View(视图)：业务逻辑层，调用Model和TemplateDjango还有一个url分发器，它的作用是将一个个URL的页面请求分发给不同的view处理，view再调用相应的Model和Template

Pytharm搭建Django项目

启动项目
1.由pycharm创建的直接单机运行按钮启动项目
2.由cmd创建，需要对该项目进行配置，如下

Django配置简介

"""
Django settings for Django project.Generated by 'django-admin startproject' using Django 2.0.2.For more information on this file, see
https://docs.djangoproject.com/en/2.0/topics/settings/For the full list of settings and their values, see
https://docs.djangoproject.com/en/2.0/ref/settings/
"""import os# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
# 项目路径
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/2.0/howto/deployment/checklist/# SECURITY WARNING: keep the secret key used in production secret!
# 秘钥配置
SECRET_KEY = 'k&czldpy&$_5t2s77s-a2u!%ok-=zc&p2&ld_66b1_k7(*!uik'# SECURITY WARNING: don't run with debug turned on in production!
# 调试模式
DEBUG = True# 域名访问权限
ALLOWED_HOSTS = ['*']# Application definition
# app列表
INSTALLED_APPS = [# 内置后台管理系统'django.contrib.admin',# 内置用户认证系统'django.contrib.auth',# 记录项目中所有model元数据（orm框架）'django.contrib.contenttypes',# Session会话功能'django.contrib.sessions',# 消息提示功能'django.contrib.messages',# 查找静态资源路径'django.contrib.staticfiles',
]MIDDLEWARE = [# 内置安全机制'django.middleware.security.SecurityMiddleware',# 会员Session功能'django.contrib.sessions.middleware.SessionMiddleware',# 中间件支持中文'django.middleware.locale.LocaleMiddleware',# 处理请求信息，规范化请求内容'django.middleware.common.CommonMiddleware',# 开启CRSF防护功能'django.middleware.csrf.CsrfViewMiddleware',# 开启内置的用户认证系统'django.contrib.auth.middleware.AuthenticationMiddleware',# 开启内置的信息提示功能'django.contrib.messages.middleware.MessageMiddleware',# 防止恶意程序点击劫持'django.middleware.clickjacking.XFrameOptionsMiddleware',
]ROOT_URLCONF = 'Django.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 = 'Django.wsgi.application'# Database
# https://docs.djangoproject.com/en/2.0/ref/settings/#databases
#数据库配置
"""
DATABASES = {'default': {'ENGINE': 'django.db.backends.sqlite3','NAME': os.path.join(BASE_DIR, 'db.sqlite3'),}
}
"""
DATABASES = {'default': {'ENGINE': 'django.db.backends.mysql','NAME': 'django','USER': 'root','PASSWORD': 'root','HOST': '192.168.250.170','PORT': '3306',},
}# Password validation
# https://docs.djangoproject.com/en/2.0/ref/settings/#auth-password-validators
#用户密码验证器
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/2.0/topics/i18n/
#配置时区，语言
LANGUAGE_CODE = 'zh-hans'TIME_ZONE = 'UTC'USE_I18N = TrueUSE_L10N = TrueUSE_TZ = True# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/2.0/howto/static-files/
# 静态文件目录
STATIC_URL = '/static/'# 设置根目录的静态资源文件夹                                   设置App（index）的静态资源文件夹
STATICFILES_DIRS = [os.path.join(BASE_DIR, 'public_static'), os.path.join(BASE_DIR, 'index/index_static')]

创建App：代表项目应用(网站的一个或多个网页)
app的创建由manage.py实现，python manage.py startapp XXX

完成index和user创建后，要配置app

使用mysql要下载mysqlclient : pip install mysqlclient
django不能创建数据库，所以要先创建好数据库。
根据model.py生成相关的.py文件，该文件用于创建数据库表
python manage.py makemigrations
创造或修改表结构
python manage.py migrate
可以在数据库看到新建的表
（顺便提一下，数据库数据迁移，可以使用主从复制）
手动添加数据

index app下views.py添加如下代码

from django.shortcuts import render# Create your views here.
from .models import Product# def index(request):
#     return HttpResponse("hello word")def index(request):type_list = Product.objects.values('type').distinct()name_list = Product.objects.values('name', 'type')# 打印执行的sqlprint(type_list.query)print(name_list.query)context = {'type_list': type_list, 'name_list': name_list}return render(request, 'index.html', context=context, status=200)

templates新建index.html

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body><ul id="cate_box">{% for type in type_list %}<li><h3>{{ type.type }}</h3><p>{% for name in name_list %}{% if name.type == type.type %}<span>{{ name.name }}</span>{% endif %}{% endfor %}</p></li>{% endfor %}</ul>
</body>
</html>

index app下urls.py添加如下代码

from django.urls import path, re_path, include
from . import viewsurlpatterns = [# 配置简单URLpath('', views.index),]

通用视图体验

Django封装常用代码，便于快速完成数据视图开发
封装的三个类
TemplateView：直接返回HTML模板，无法展示数据库数据。
ListView：能将数据库数据返回给HTML模板，通常获取批量数据。
DetailView：能将数据库数据返回给HTML模板，通常获取单条数据。

view.py

from django.shortcuts import render# Create your views here.
from .models import Product
from django.http import HttpResponse
from django.views.generic import ListViewclass ProductList(ListView):content_object_name = "type_list"template_name = "index.html"# django.core.exceptions.ImproperlyConfigured: ProductList is missing a QuerySet. Define ProductList.model, ProductList.queryset, or override ProductList.get_queryset().queryset = Product.objects.values('type').distinct()# def get_queryset(self):#     return Product.objects.values('type').distinct()def get_context_data(self, queryset=queryset, **kwargs):context = super().get_context_data(**kwargs)context['name_list'] = Product.objects.values('name', 'type')context['type_list'] = querysetreturn context

urls.py

from . import views
from django.conf.urls import urlurlpatterns = [# 通用视图url(r'^index/$', views.ProductList.as_view()),
]