ContentType 模型对应数据库中django_content_type表,主要用户维护 django project 中所安装的所有用户模型

代码如下:

class ContentType(models.Model):
   #这三个字段分别表示 模型的用户化名称,模型所属app名称,模型名称
name
= models.CharField(max_length=100,verbose_name=_('name'))
app_label
= models.CharField(max_length=100)
model
= models.CharField(_('python model class name'), max_length=100)
objects
= ContentTypeManager()  #自定义Mananger类

class Meta:
verbose_name
= _('content type')
verbose_name_plural
= _('content types')
db_table
= 'django_content_type'
ordering
= ('name',)
unique_together
= (('app_label', 'model'),)

def __unicode__(self):
return self.name

def model_class(self):
"Returns the Python model class for this type of content."
from django.db import models
return models.get_model(self.app_label, self.model)

def get_object_for_this_type(self, **kwargs):
"""
Returns an object of this type for the keyword arguments given.
Basically, this is a proxy around this object_type's get_object() model
method. The ObjectNotExist exception, if thrown, will not be caught,
so code that calls this method should catch it.
"""
return self.model_class()._default_manager.using(self._state.db).get(**kwargs)

def natural_key(self):
return (self.app_label, self.model)