创建应用

1 创建project

Django-admin startproject mysite

自动创建目录结构:

mysite/    #项目容器

Manage.py    #命令行工具

mysite/   #项目文件

__init__.py   #定义包的空文件

Settings.py   #配置文件

Urls.py  #路由文件

Wsgi.py #提供底层网络通信

2 启动服务器

Python manage.py runserver

查看运行

http://127.0.0.1:8000/

3 创建应用程序

Python manage.py polls

4 编写视图

from django.test import TestCase
from django.http import HttpResponse

# Create your tests here.
def index(request):
return HttpResponse('Hello,word!You are at the polls index')

新建urls.py

from django.conf.urls import url
from . import views

urlpatterns = [
    url(r'^$',views.index,name='index')
]

修改mysite/urls.py,添加如下内容:

from django.conf.urls import include

urlpatterns = [

url(r'^polls/',include('polls.urls')),

]

启动服务器

Python manage.py runserver

通过浏览器查看

http://127.0.0.1:8000/polls/

5 数据库安装

本示例使用的是mysql数据库.也可以使用其他,对应的配置如下:

Sqlite ’django.db.backends.sqlite3’

Postgresql ’django.db.backends.postgresql’,

Mysql ’django.db.backends.mysql’

Oracle ’django.db.backends.oracle’，

,修改mysite/setting.py,

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

#mysql
'ENGINE':'django.db.backends.mysql',#引擎
'NAME':'jkx',#数据库名
'USER':'root',#用户名
'PASSWORD':'yue4512138',#密码
'HOST':'127.0.0.1',#数据库服务器ip
'PORT':'3306',#端口号
}
}

6 创建model模型

Polls/model.py

每个模型对应数据库中的一张表

'''
问题
'''
class Question(models.Model):
    question_text=models.CharField(max_length=200)
    pub_date=models.DateTimeField('date published')

'''
选票
'''
class Choice(models.Model):
    question=models.ForeignKey(Question,on_delete=models.CASCADE)
    choice_text=models.CharField(max_length=200)
    votes=models.IntegerField(default=0)

7 注册应用

Mysite/settings.py

INSTALLED_APPS = [
'django.contrib.admin',#admin站点
'django.contrib.auth',#身份话证系统
'django.contrib.contenttypes',#内容类型框架
'django.contrib.sessions',#会话框架
'django.contrib.messages',#消息框架
'django.contrib.staticfiles',#静态文件管理框架
'polls.apps.PollsConfig'
]

重新生成模型的数据表结构,为改动创建迁移记录

python manage.py makemigrations polls

对数据库进行真正的迁移

Python manage.py sqlmigrate polls 0001

//在不丢失数据的同时,实时动态更新数据库

python manage.py migrate

8 使用api

D:\workspace_python\mysite>python manage.py shell

Python 3.6.0b2 (v3.6.0b2:b9fadc7d1c3f, Oct 10 2016, 20:36:51) [MSC v.1900 32 bit (Intel)] on win32

Type "help", "copyright", "credits" or "license" for more information.

(InteractiveConsole)

>>>

>>> import django

>>> django.setup()#重启django

>>> from polls.models import Question,Choice#导入操作模块

>>> Question.objects.all()#查询question列表

<QuerySet []>

>>> from django.utils import timezone#导入模块

>>> q=Question(question_text="What is your name?",pub_date=timezone.now())#创建question对象

>>> q.save()#保存到数据库中

>>> q.id

1

>>> q.question_text

'What is your name?'

>>> q.pub_date

datetime.datetime(2016, 10, 21, 9, 34, 11, 36818, tzinfo=<UTC>)

>>> q.question_text='what is up?'#修改属性值

>>> q.save()#保存到数据库中

>>> Question.objects.all()#查询问题列表

<QuerySet [<Question: Question object>]>#看不到问题详细

需要修改model.py

两个模型中分别添加:

#想使用python2版本时才能使用
from django.utils.encoding import

python_2_unicode_compatible

def __str__(self):#python2版本中使用的是__unique__
return self.question_text

def __str__(self):
return self.choice_text

修改完成后,重新启动shell

>>> from polls.models import Question,Choice

>>> Question.objects.all()

<QuerySet [<Question: what is up?>]>

>>> Question.objects.filter(id=1)

<QuerySet [<Question: what is up?>]>

>>> Question.objects.filter(question_text__startswith='what')

<QuerySet [<Question: what is up?>]>

>>> from django.utils import timezone

>>> current_year=timezone.now().year

>>> Question.objects.get(pub_date__year=current_year)

<Question: What is your name?>

>>> Question.objects.get(id=2)

Traceback (most recent call last):

File "<console>", line 1, in <module>

File "D:\Python36\lib\site-packages\django\db\models\manager.py", line 85, in manager_method

return getattr(self.get_queryset(), name)(*args, **kwargs)

File "D:\Python36\lib\site-packages\django\db\models\query.py", line 385, in get

self.model._meta.object_name

polls.models.DoesNotExist: Question matching query does not exist.

>>> q.choice_set.all()#查询关系集合

<QuerySet []>

#创建三个choice对象

>>> q.choice_set.create(choice_text='Not much',votes=0)

<Choice: Not much>

>>> q.choice_set.create(choice_text='The sky',votes=0)

<Choice: The sky>

>>> q.choice_set.create(choice_text='Just hacking again',votes=0)

<Choice: Just hacking again>

>>> q.choice_set.all()#查询choice列表

<QuerySet [<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking again>]>