Question

在我们的应用程序中，我们的模型A包含泛型关系的字段，因为它可能与两个模型之一（B或C）的实例相关

填充非泛型ForeignKey字段时，我们可以使用ModelChoiceField。我们的问题是我们找不到MultipleModelsChoiceField，其选择将从B和C的查询集中填充。

如何通过重用尽可能多的现有Django代码来解决这个问题？

Answer 1

您可以这样做：

class YourForm(forms.ModelForm):
    your_field = forms.ChoiceField()

    def __init__(self, *args, **kwargs):
        super(YourForm, self).__init__(*args, **kwargs)
        your_generic_relations_objects = list(FirtsModel.object.all()) + list(SecondModel.objects.all())  # and etc
        object_choices = []
        for obj in your_generic_relations_objects:
            type_id = ContentType.objects.get_for_model(obj.__class__).id
            obj_id = obj.id
            form_value = 'type:%s-id:%s' % (type_id, obj_id)
            display_text = str(obj)
            object_choices.append([form_value, display_text])
        self.fields['your_field'] = forms.ChoiceField(choices=object_choices)

    class Meta:
        model = YourModel
        fields = [
            'your_field'  # and others
        ]

    def save(self, *args, **kwargs):
        object_string = self.cleaned_data['your_field']
        matches = re.match("type:(\d+)-id:(\d+)", object_string).groups()
        content_type_id = matches[0]
        object_id = matches[1]
        content_type = ContentType.objects.get(id=content_type_id)
        self.instance.object_id = object_id
        self.instance.content_type = content_type
        return super(YourForm, self).save()

在Django中，如何从单个表单字段填充泛型关系？

1 个答案: