Question

我有一个模型，我将其用作创建另一个模型的参考点：

class ImYourFather(models.Model):
    force = fields.HTMLField(null=True, blank=True)
    supermarket_planets = models.HTMLField(null=True, blank=True)
    destroying_planets = models.HTMLField()

class Luke(ImYourFather):
    # Inheriting all the fields from father
    the_cool_kid = models.HTMLField() # extra field added

我不要想要继承destroying_planets字段，这可能吗？
我具体问的是因为destroying_planets在父模型中应该是强制，但我想在子模型中使用可选。 /> 这是以另一种方式实现的吗？

Answer 1

您无法部分继承，但可以使用所需的任何字段手动创建模型。这与multi-table inheritance不完全相同，但这是部分继承字段的唯一方法：

class Base(models.Model):
    force = fields.HTMLField(null=True, blank=True)
    supermarket_planets = models.HTMLField(null=True, blank=True)

    class Meta(object):
        abstract = True

class ImYourFather(Base):
    destroying_planets = models.HTMLField()

class Luke(Base):
    # optional in case you need this
    father = models.OneToOneField(ImYourFather, related_name='lukes')
    the_cool_kid = models.HTMLField() # extra field added

修改

另一种方法是简单地复制父亲的字段。这都是未经测试的，所以Django可能会嘲笑你的一些）。优点是没有猴子修补但应该工作：

exclude = ['id', 'destroying_planets'] try: # Django 1.7 fields = {i.attname: i.clone() for i in ImYourFather._meta.fields if not i.attname in exclude} except AttributeError: # Django < 1.7 fields = {i.attname: deepcopy(i) for i in ImYourFather._meta.fields if not i.attname in exclude} Base = type('Base', (models.Model,), fields) class Luke(Base): # optional in case you need this father = models.OneToOneField(ImYourFather, related_name='lukes') the_cool_kid = models.HTMLField() # extra field added

Django中的部分模型继承

1 个答案: