django创建项目案例1详细介绍方法01

       
django版本1.8.2
pip install django==1.8.2
设计介绍
本示例完成“图书-英雄”信息的维护，需要存储两种数据：图书、英雄
图书表结构设计：
表名：BookInfo
图书名称：btitle
图书发布时间：bpub_date
英雄表结构设计：
表名：HeroInfo
英雄姓名：hname
英雄性别：hgender
英雄简介：hcontent
所属图书：hbook
图书-英雄的关系为一对多
数据库配置
在settings.py文件中，通过DATABASES项进行数据库设置
django支持的数据库包括：sqlite、mysql等主流数据库
Django默认使用SQLite数据库

命令django-admin startproject test1
进入test1目录，目录结构如下图：

2018-07-17 00-19-45屏幕截图.png

image.png

目录说明
manage.py：一个命令行工具，可以使你用多种方式对Django项目进行交互
内层的目录：项目的真正的Python包
_init _.py：一个空文件，它告诉Python这个目录应该被看做一个Python包
settings.py：项目的配置
urls.py：项目的URL声明
wsgi.py：项目与WSGI兼容的Web服务器入口

创建应用
在一个项目中可以创建一到多个应用，每个应用进行一种业务处理
创建应用的命令：python manage.py startapp booktest
应用的目录结构如下图

image.png

image.png

d3.png

定义模型类models.py

有一个数据表，就有一个模型类与之对应
打开models.py文件，定义模型类
引入包from django.db import models
模型类继承自models.Model类
说明：不需要定义主键列，在生成时会自动添加，并且值为自动增长
当输出对象时，会调用对象的str方法

代码如下:

from django.db import models

# Create your models here.

class BookInfo(models.Model):
    btitle=models.CharField(max_length=20)
    bpub_date=models.DateTimeField()
    def __str__(self):
        return self.btitle.encode('utf-8')


class HeroInfo(models.Model):
    hname=models.CharField(max_length=10)
    hgender=models.BooleanField()
    hcontent=models.CharField(max_length=1000)
    hbook=models.ForeignKey(BookInfo)
    def __str__(self):
        return self.hname.encode('utf-8')

然后

(python2) linux@ubuntu:~/桌面/project/test1$ python manage.py runserver 8080

生成数据表

• 激活模型：编辑settings.py文件，将booktest应用加入到installed_apps中

INSTALLED_APPS = (
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'booktest'
)

• 生成迁移文件：根据模型类生成sql语句

python manage.py makemigrations

(python2) linux@ubuntu:~/桌面/project/test1$ python manage.py makemigrations
Migrations for 'booktest':
  0001_initial.py:
    - Create model BookInfo
    - Create model HeroInfo
/home/linux/.virtualenvs/python2/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py:302: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
  return name == ":memory:" or "mode=memory" in force_text(name)

(python2) linux@ubuntu:~/桌面/project/test1$ ^C

• 迁移文件被生成到应用的migrations目录

  
  
  

  image.png
• 执行迁移：执行sql语句生成数据表

python manage.py migrate

(python2) linux@ubuntu:~/桌面/project/test1$ python manage.py migrate
Operations to perform:
  Synchronize unmigrated apps: staticfiles, messages
  Apply all migrations: admin, contenttypes, sessions, auth, booktest
Synchronizing apps without migrations:
  Creating tables...
    Running deferred SQL...
  Installing custom SQL...
/home/linux/.virtualenvs/python2/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py:302: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
  return name == ":memory:" or "mode=memory" in force_text(name)

Running migrations:
  Rendering model states... DONE
  Applying contenttypes.0001_initial... OK
  Applying auth.0001_initial... OK
  Applying admin.0001_initial... OK
  Applying contenttypes.0002_remove_content_type_name... OK
  Applying auth.0002_alter_permission_name_max_length... OK
  Applying auth.0003_alter_user_email_max_length... OK
  Applying auth.0004_alter_user_username_opts... OK
  Applying auth.0005_alter_user_last_login_null... OK
  Applying auth.0006_require_contenttypes_0002... OK
  Applying booktest.0001_initial... OK
  Applying sessions.0001_initial... OK
(python2) linux@ubuntu:~/桌面/project/test1$ 

测试数据操作

• 进入python shell，进行简单的模型API练习

python manage.py shell

• 进入shell后提示如下：

(python2) linux@ubuntu:~/桌面/project/test1$ python manage.py shell
Python 2.7.15rc1 (default, Apr 15 2018, 21:51:34) 
[GCC 7.3.0] on linux2
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from booktest.models import *
>>> b=BookInfo()
>>> b.btitle='abc'
>>> from datetime import datetime
>>> b.bpub_date=datetime(year=1990,month=1,day=12)
>>> b.save()
/home/linux/.virtualenvs/python2/lib/python2.7/site-packages/django/db/models/fields/__init__.py:1474: RuntimeWarning: DateTimeField BookInfo.bpub_date received a naive datetime (1990-01-12 00:00:00) while time zone support is active.
  RuntimeWarning)

# 查询所有图书信息：
>>> BookInfo.objects.all()
[]
>>> b=BookInfo.objects.get(pk=1)
>>> b.btitle='123'
>>> b.save()
>>> BookInfo.objects.all()
[]

# 删除
>>> b.delete()
>>> BookInfo.objects.all()
[]

按Ctrl+d退出shell

使用django的管理

• 创建一个管理员用户

python manage.py createsuperuser，按提示输入用户名、邮箱、密码

• 启动服务器，通过“127.0.0.1:8000/admin”访问，输入上面创建的用户名、密码完成登录
• 进入管理站点，默认可以对groups、users进行管理

(python2) linux@ubuntu:~/桌面/project/test1$ python manage.py createsuperuser
Username (leave blank to use 'linux'): abc
Email address: [email protected]
Password: 123
Password (again): 123
Superuser created successfully.
/home/linux/.virtualenvs/python2/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py:302: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
  return name == ":memory:" or "mode=memory" in force_text(name)



(python2) linux@ubuntu:~/桌面/project/test1$ python manage.py runserver
Performing system checks...

System check identified no issues (0 silenced).
July 17, 2018 - 09:50:32
Django version 1.8.2, using settings 'test1.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.

• 在浏览器浏览(http://127.0.0.1:8000/admin/login/?next=/admin/)
  
  

  image.png
  
  
  

  image.png

管理界面本地化

• 编辑settings.py文件，设置编码、时区

LANGUAGE_CODE = 'zh-Hans'  # 'en-us'

TIME_ZONE = 'Asia/Shanghai'  # 'UTC'

USE_I18N = True

USE_L10N = True

USE_TZ = True

向admin注册booktest的模型

• 打开booktest/admin.py文件，注册模型

from django.contrib import admin
from models import *

# Register your models here.


admin.site.register(BookInfo)
admin.site.register(HeroInfo)

• 刷新管理页面，可以对BookInfo的数据进行增删改查操作
• 问题：如果在str方法中返回中文，在修改和添加时会报ascii的错误

• 解决：在str()方法中，将字符串末尾添加“.encode('utf-8')”

  
  
  

  image.png
  
  
  

  image.png
  
  
  

  image.png

自定义管理页面

• Django提供了admin.ModelAdmin类
• 通过定义ModelAdmin的子类，来定义模型在Admin界面的显示方式

class QuestionAdmin(admin.ModelAdmin):
    ...
admin.site.register(Question, QuestionAdmin)

列表页属性

• list_display：显示字段，可以点击列头进行排序

list_display = ['pk', 'btitle', 'bpub_date']

• list_filter：过滤字段，过滤框会出现在右侧

list_filter = ['btitle']

• search_fields：搜索字段，搜索框会出现在上侧

search_fields = ['btitle']

• list_per_page：分页，分页框会出现在下侧

list_per_page = 10

添加、修改页属性

• fields：属性的先后顺序

fields = ['bpub_date', 'btitle']

• fieldsets：属性分组

fieldsets = [
    ('basic',{'fields': ['btitle']}),
    ('more', {'fields': ['bpub_date']}),
]

修改admin.py

from django.contrib import admin
from models import *

# Register your models here.


class BookInfoAdmin(admin.ModelAdmin):
    list_display = ['id','btitle','bpub_date']
    list_filter = ['btitle']
    search_fields = ['btitle']
    list_per_page = 1
    fieldsets = [
        ('base',{'fields':['btitle']}),
        ('super',{'fields':['bpub_date']})
    ]


admin.site.register(BookInfo,BookInfoAdmin)
admin.site.register(HeroInfo)

效果图

image.png