django - 通用 DeleteView 在 0x04725628 处返回 django.db.models.query_utils.DeferredAttribute 对象 - Django

Question

免责声明:我只是一个尝试学习 Django 的新手
您好，我正在尝试重构我的代码并将我创建的所有 View 修改为基于类的 View 。
我在加载带有 DeleteView 的表单时遇到问题，该表单显示数据但同时被禁用。
我取得了一些成功，唯一不知道该怎么做的是显示数据而不是现在出现的消息“ ”
+models.py:

class Note(models.Model):
title = models.CharField(max_length=30)
image_url = models.URLField()
content = models.TextField()
owner = models.ForeignKey(Profile, default=8, on_delete=models.CASCADE)

def get_absolute_url(self):
    return reverse(self.pk)

def __str__(self):
    return f'{self.title}'

+forms.py

class NoteForm(forms.ModelForm):
class Meta:
    model = Note
    exclude = ('owner',)


class DeleteNoteForm(NoteForm):
def __init__(self, *args, **kwargs):
    super().__init__(*args, **kwargs)
    for (_, field) in self.fields.items():
        field.widget.attrs['readonly'] = True
        field.widget.attrs['disabled'] = True

+views.py

class DeleteNoteView(DeleteView):
model = Note
template_name = 'note-delete.html'
form_class = DeleteNoteForm
success_url = reverse_lazy('home page')

def get_context_data(self, **kwargs):
    data = super().get_context_data(**kwargs)
    data['form'] = self.form_class(instance=self.model)
    return data

+urls.py

path('delete/<int:pk>/', views.DeleteNoteView.as_view(), name='delete note'),

+模板

        <!--note delete data form-->
    <div class="form">
        <form method="POST">
            {{ form }}
            {% csrf_token %}
            <input type="submit" value="Delete"/>
        </form>
    </div>
    <!--end note delete data form-->

如果我使用我的 View 它工作正常，但我想修改它。

def delete_note(request, pk):
note = Note.objects.get(pk=pk)
if request.method=='GET':
    note_form = DeleteNoteForm(instance=note)
    context = {
        'note_form': note_form
    }
    return render(request, 'note-delete.html', context)
else:
    note.delete()
    return redirect('home page')

有人可以告诉我我错在哪里以及如何解决它，或者至少为我提供一个包含信息的链接以了解为什么会发生这种情况？

Answer 1

您正在传递对 DeleteNoteView 中的模型类的引用。 ，而您应该使用已删除的对象，因此:

class DeleteNoteView(DeleteView):
    model = Note
    template_name = 'note-delete.html'
    form_class = DeleteNoteForm
    success_url = reverse_lazy('home page')
    
    def get_context_data(self, **kwargs):
        data = super().get_context_data(**kwargs)
        #       user self.object instead of self.model ↓
        data['form'] = self.form_class(instance=self.object)
        return data

我还建议过滤 QuerySet这样其他用户(不是 Note 的所有者的用户)不可能删除该 Note :

from django.contrib.auth.mixins import LoginRequiredMixin

class DeleteNoteView(LoginRequiredMixin, DeleteView):
    model = Note
    template_name = 'note-delete.html'
    form_class = DeleteNoteForm
    success_url = reverse_lazy('home page')

    def get_queryset(self, *args, **kwargs):
        return super().get_queryset(*args, **kwargs).filter(
            owner=self.request.user
        )
    
    def get_context_data(self, **kwargs):
        data = super().get_context_data(**kwargs)
        data['form'] = self.form_class(instance=self.object)
        return data