Question

我有一个Model，其中UUID为pk。

class Product(models.Model):
    uuid = models.UUIDField(
        primary_key=True, 
        default=uuid.uuid4, 
        editable=False)

我需要使用ModelForm编辑其他一些字段，并且需要在POST数据中提交UUID以识别Product。目前，我得到了：

django.core.exceptions.FieldError: 'uuid' cannot be specified for Product model form as it is a non-editable field

显然，我可以让这个字段不可编辑，以便快速解决这个问题。然而，在我看来，拒绝对该字段的写访问应该发生在比ModelForm更低的逻辑级别（即我认为应该在尝试编辑它时引发异常）。是否可以这样做呢？

编辑：清理回溯

  File "/webapps/myapp/urls.py", line 6, in <module>
    from my_app import views
  File "/webapps/myapp/views/__init__.py", line 2, in <module>
    from .my_view import MyView
  File "/webapps/myapp/views/my_view.py", line 12, in <module>
    from my_app.forms import ProductForm
  File "/webapps/myapp/forms.py", line 5, in <module>
    class ProductForm(forms.ModelForm):
  File "/webapps/myapp/lib/python3.5/site-packages/django/forms/models.py", line 242, in __new__
    opts.field_classes)
  File "/webapps/myapp/lib/python3.5/site-packages/django/forms/models.py", line 138, in fields_for_model
    f.name, model.__name__)
django.core.exceptions.FieldError: 'uuid' cannot be specified for Product model form as it is a non-editable field

表格代码：

class ProductForm(forms.ModelForm):
    uuid = forms.UUIDField(required=False, widget=forms.HiddenInput())

Answer 1

指定表单的instance argument以更改现有对象：

def edit_product(request, uuid):
    product = get_object_or_404(Product, uuid=uuid)
    ...
    if request.method == 'POST':
        form = ProductForm(request.POST, instance=product)
        if form.is_valid():
            form.save()
            ...

在POST数据中需要一个不可编辑的字段，但ModelForm不允许我这样做

1 个答案: