Question

我有以下型号：

class Series(models.Model):
    item_id = models.CharField(max_length=60, unique=True, blank=True)
    name = models.CharField(max_length=600, blank=True)

    def save(self, *args, **kwargs):
        super(self.__class__, self).save(*args, **kwargs)
        if not self.item_id:
            self.item_id = '%s%s' % (self.__class__.__name__[0], self.pk)
            self.save()

我已经创建了这个通用的保存方法，我也想将其应用到其他模型中。我如何在models.py文件中执行此操作？

Answer 1

2个选项（两者都非常相似，它们以微妙的方式变化）：

创建父类：

class MyModel(models.Model):
    """My Custom Model Class"""
    def save(self, *args, **kwargs):
        super(self.__class__, self).save(*args, **kwargs)
        if not self.item_id:
            self.item_id = '%s%s' % (self.__class__.__name__[0], self.pk)
            self.save()
    # Must make the parent Model abstract to avoid table creation
    class Meta:
        abstract = True

class Series(MyModel):
    item_id = models.CharField(max_length=60, unique=True, blank=True)
    name = models.CharField(max_length=600, blank=True)

创建一个Mixin

class MySaveMixin(object):
    """My Mixin for providing save functionality to Models"""
    def save(self, *args, **kwargs):
        super(self.__class__, self).save(*args, **kwargs)
        if not self.item_id:
            self.item_id = '%s%s' % (self.__class__.__name__[0], self.pk)
            self.save()

class Series(models.Model, MySaveMixin):
    item_id = models.CharField(max_length=60, unique=True, blank=True)
    name = models.CharField(max_length=600, blank=True)

如何为所有模型添加相同的保存方法

1 个答案: