文档似乎很确定确实如此。
https://docs.djangoproject.com/en/dev/topics/forms/modelforms/#the-save-method
我特指此部分:
我对django很陌生,昨天偶然发现了这些信息。
但是,我有一个 View ,在这里我不调用save_m2m()方法,但实际上保存了m2m数据。
这是我的看法:
class SubscriberCreateView(AuthCreateView):
model = Subscriber
template_name = "forms/app.html"
form_class = SubscriberForm
success_url = "/app/subscribers/"
def get_form_kwargs(self):
kwargs = super(SubscriberCreateView, self).get_form_kwargs()
kwargs.update({'user': self.request.user})
return kwargs
def form_valid(self, form):
self.object = form.save(commit=False)
self.object.user = self.request.user
try:
self.object.full_clean()
except ValidationError:
form._errors["email"] = ErrorList([u"This subscriber email is already in your account."])
return super(SubscriberCreateView, self).form_invalid(form)
return super(SubscriberCreateView, self).form_valid(form)
我的模特:class Subscriber(models.Model):
STATUS_CHOICES = (
(1, ('Subscribed')),
(2, ('Unsubscribed')),
(3, ('Marked as Spam')),
(4, ('Bounced')),
(5, ('Blocked')),
(6, ('Disabled')),
)
user = models.ForeignKey(User)
status = models.IntegerField(('status'), choices=STATUS_CHOICES, default=1)
email = models.EmailField()
subscriber_list = models.ManyToManyField('SubscriberList')
first_name = models.CharField(max_length=70, blank=True)
last_name = models.CharField(max_length=70, blank=True)
phone = models.CharField(max_length=20, blank=True)
facebook_id = models.CharField(max_length=40, blank=True)
twitter_id = models.CharField(max_length=40, blank=True)
address1 = models.CharField(max_length=100, blank=True)
address2 = models.CharField(max_length=100, blank=True)
postcode = models.CharField(max_length=10, blank=True)
city = models.CharField(max_length=30, blank=True)
country = models.CharField(max_length=30, blank=True)
date_joined = models.DateTimeField(auto_now_add=True)
date_updated = models.DateTimeField(auto_now=True)
class Meta:
unique_together = (
('user', 'email',),
)
def __unicode__(self):
return self.email
我的表格:class SubscriberForm(ModelForm):
def __init__(self, user, *args, **kwargs):
super (SubscriberForm, self).__init__(*args, **kwargs)
self.fields['subscriber_list'].queryset = SubscriberList.objects.filter(user=user)
class Meta:
model = Subscriber
exclude = ('user', 'facebook_id', 'twitter_id')
那么,为什么我的 View 起作用? (这意味着,在处理表单时,实际上保存了表单中字段之一的m2m关系。) 最佳答案
父类之一正在执行模型对象及其m2m关系的完整保存。我不确定,因为我没有AuthCreateView
的声明,但是命名约定表明它起源于“CreateView”。如果是这样,则View的继承就是SubscriberCreateView -> AuthCreateView -> CreateView -> BaseCreateView -> ModelFormMixin
。 ModelFormMixin具有 form_valid()
方法,您(可能)使用调用super()
。
这是Django 1.4中的整个method:
def form_valid(self, form):
self.object = form.save()
return super(ModelFormMixin, self).form_valid(form)
所以你有它。但是,让我指出一些潜在的困惑。当指出您不保存对象时,@ Wogan非常聪明。按照代码的方式,您可以使用未保存的模型实例进行验证,然后将其丢弃,因为ModelFormMixin重新分配了
self.object
。self.object
可能与以后访问时所期望的不一样。 self.object.user
信息。 (因为user
是模型上的必填字段,并且您将其排除在表单中,所以我希望save()
失败。因此父AuthCreateView
必须正在执行某些操作。 。)为了避免这种困惑,只需不将实例分配给
save()
即可。也许:ModelFormMixin