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Django模型形式继承和元继承

django-forms inheritance django python

Mike Vlad · 技术社区 · 6 年前

我有这个模型:

class Event(forms.ModelForm):

    def __init__(self, *args, **kwargs):
        super(Event, self).__init__(*args, **kwargs)
        ##Here make some changes such as:
        self.helper = FormHelper()
        self.helper.form_method = 'POST'
        ##Many settings here which **i don't want to rewrite in 10 child classes**

    class Meta:
        model = Event
        exclude = something...
        widgets = some settings here also.

这个子模型:

class UpgradedEvent(Event):

    def __init__(self, *args, **kwargs):
        super(UpgradedEvent,self).__init__(*args,**kwargs)

    class Meta(Event.Meta):
        model = UpgradedEvent

UpgradedEvent 他是个孩子 Event 模型但是有一些额外的字段。我如何从服务器继承所有设置 事件 形成 升级 类型

当运行上述代码时,它会呈现 事件 类型有没有办法只继承里面的设置 __init__ ?

编辑

请查看答案,它非常有效,但请记住: 您需要创建另一个 FormHelper 在你的孩子课堂上,否则就不行了。所以儿童班应该是这样的:

class UpgradedEvent(Event):

    def __init__(self, *args, **kwargs):
        super(UpgradedEvent,self).__init__(*args,**kwargs)
        self.helper = FormHelper()

    class Meta(Event.Meta):
        model = UpgradedEvent

2 回复 | 直到 6 年前

Sardorbek Imomaliev 6 年前

你可以在 Meta 并扩展列表等:

class UpgradedEventForm(EventForm):

    def __init__(self, *args, **kwargs):
        super(UpgradedEventForm,self).__init__(*args,**kwargs)
        # some extra settings
        # ...
        # for example
        self.fields['extra_field'].initial = 'initial value of extra field'

    class Meta(EventForm.Meta):
        model = UpgradedEvent
        exclude = EventForm.Meta.exclude + ['extra_exclude1', 'extra_exclude2']
        fields = EventForm.Meta.fields + ['extra_field']

因此,通过使用继承,我们可以向 __init__ 通过在 super(UpgradedEventForm, self) 调用,wwe可以访问父级的属性,并扩展这些属性。

请注意,您最好使用 Form 后缀,因为现在你的模型和你的表格冲突了。因此,你的 类型 似乎有一个参考模型 类型 它本身“正确使用” 命名法 “,你避免了很多错误。

willeM_ Van Onsem 6 年前

创造 FormWithSettings 它将保存窗体类的公共设置并继承它

class FormWithSettings(forms.ModelForm):

    def __init__(self, *args, **kwargs):
        super(FormWithSettings, self).__init__(*args, **kwargs)
        ##Here make some changes such as:
        self.helper = FormHelper()
        self.helper.form_method = 'POST'
        ##Many settings here which **i don't want to rewrite in 10 child classes**

    class Meta:
        exclude = something...
        widgets = some settings here also.

class EventForm(FormWithSettings):

    def __init__(self, *args, **kwargs):
        super(EventForm, self).__init__(*args,**kwargs)

    class Meta(FormWithSettings.Meta):
        model = Event

class UpgradedEventForm(FormWithSettings):

    def __init__(self, *args, **kwargs):
        super(UpgradedEventForm, self).__init__(*args,**kwargs)

    class Meta(FormWithSettings.Meta):
        model = UpgradedEvent