Django：＆＃34; Model2.user＆＃34;必须是＆＃34;用户＆＃34;例

Question

我有以下型号：

class Model1(models.Model):
    Field1 = models.CharField(max_length=200)

class Model2(models.Model)
    Field2 = models.ForeignKey(Model1, on_delete=models.CASCADE)
    Field3 = models.ForeignKey(User, on_delete=models.CASCADE)
    Email = models.EmailField(null=TRUE)

这是forms.py：

class Model1Form(ModelForm):
    class Meta:
        model = Model1
        fields = ['Field1']

class Model2Form(ModelForm):
    class Meta:
        model = Model2
        fields = ['email']


Model2Field2Formset = inlineformset_factory(Model1, Model2, form=Model2Form, extra=1)
Model2Field3Formset = inlineformset_factory(User, Model2, form=Model2Form, extra=1)

这是views.py：

class NewEntry(CreateView):
    model = Model1
    fields = ['Field1']
    success_url = reverse_lazy('voting:index')

    def get_context_data(self, **kwargs):
        data = super().get_context_data(**kwargs)
        if self.request.POST:
            data['model2_field2'] = Model2Field2Formset(self.request.POST)
            data['model2_field3'] = Model2Field3Formset(self.request.POST)
        else:
            data['model2_field2'] = Model2Field2Formset()
            data['model2_field3'] = Model2Field3Formset()
        return data

    def form_valid(self, form):
        context = self.get_context_data()
        model2_field2 = context['model2_field2']
        model2_field3 = context['model2_field3']
        with transaction.atomic():
            self.object = form.save()
            if model2_field2.is_valid() and model2_field3.is_valid():
                model2_field2.instance = self.object
                model2_field2.save()
                model2_field3.instance = self.object
                model2_field3.save()

        return super().form_valid(form)

我正在尝试为Model1，Field1创建一个条目。然后，使用inlineformset_factory在email中创建多个Model2条目，每个条目与相同的Field1_id条目相关联，并且每个条目user_id email在表单中。

但我得到"Model2.user" must be a "User" instance。 model2_field3.save()代码行上的错误。 如果我注释掉该行没有错误，则条目会按预期保存，但Field3列仍为NULL。

这是错误的追溯：

Environment:


Request Method: POST
Request URL: http://127.0.0.1:8000/polls/newpoll/

Django Version: 2.0.5
Python Version: 3.5.2
Installed Applications:
['secvot',
 'accounts.apps.AccountsConfig',
 'voting.apps.VotingConfig',
 'django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware']



Traceback:

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/core/handlers/exception.py" in inner
  35.             response = get_response(request)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/core/handlers/base.py" in _get_response
  128.                 response = self.process_exception_by_middleware(e, request)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/core/handlers/base.py" in _get_response
  126.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/views/generic/base.py" in view
  69.             return self.dispatch(request, *args, **kwargs)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/views/generic/base.py" in dispatch
  89.         return handler(request, *args, **kwargs)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/views/generic/edit.py" in post
  172.         return super().post(request, *args, **kwargs)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/views/generic/edit.py" in post
  142.             return self.form_valid(form)

File "/home/kostis/PycharmProjects/secvot/voting/views.py" in form_valid
  110.                 eligible_voters_user.save()

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/forms/models.py" in save
  670.         return self.save_existing_objects(commit) + self.save_new_objects(commit)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/forms/models.py" in save_new_objects
  804.             self.new_objects.append(self.save_new(form, commit=commit))

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/forms/models.py" in save_new
  943.         setattr(form.instance, self.fk.name, self.instance)

File "/home/kostis/.virtualenvs/secvote/lib/python3.5/site-packages/django/db/models/fields/related_descriptors.py" in __set__
  197.                     self.field.remote_field.model._meta.object_name,

Exception Type: ValueError at /polls/newpoll/
Exception Value: Cannot assign "<Poll: asdefrgrs>": "EligibleVoters.user" must be a "User" instance.

只是旁注，EligibleVoters模型在我的问题中是相应的Model2。我重命名并删除了一些字段以使我的问题更简单。

这就是我想要实现的目标：

基本上是一个带有两个外键的模型（两个父模型）。 创建一个Field1条目，然后使用inlineformset_factory在与email条目相关联的Model2条目中创建多个Field1条目以及相应的user_id每个email。

Answer 1

在form_valid()方法中，您将同一self.object分配给model2_field2和model2_field3，这可能不正确，因为它们是不同模型的外键。您很可能尝试将Model1的实例分配给model2_field3，您应该在该字段中为User分配add_filter('loop_shop_columns', 'loop_columns'); if (!function_exists('loop_columns')) { function loop_columns() { if ( is_product_category('torres-elevadoras')) { // wanted product category return 2; } } 的实例。