Python 如何查询/过滤M2M'；通过'；Django中的对象

我有以下基本模型

  class Campaign(models.Model):
    name = models.CharField(_('name'), max_length=80, unique=True)
    recipients = models.ManyToManyField('Person', blank=True, null=True, through='Recipient')


  class Recipient(models.Model):
    campaign = models.ForeignKey(Campaign)
    person = models.ForeignKey('Person')


  class Person(models.Model):
    first_name = models.CharField(_('first name'), max_length=30, blank=True)
    last_name = models.CharField(_('last name'), max_length=30, blank=True)

我希望有一个查询集，用于查询不在给定活动中的所有Person对象

如果能像这样简单就好了：

Person.objects.all().exclude(<mycampaign>.recipients.all())

---

我相信这会成功的

from django.db.models import Q
Person.objects.filter(~Q(id__in=<mycampaign>.recipients.all())

从django.db.models导入Q
Person.objects.filter（~Q（id\uu in=.recipients.all（））

答案是这样的……问题是我的表单是针对收件人对象而不是活动对象的……Furbeenator的答案是朝着正确方向迈出的一大步……还有一些关于django IRC的帮助

class RecipientsForm(forms.ModelForm):

  def __init__(self, *args, **kwargs):
    self.campaign = kwargs.pop('campaign', None)
    super(RecipientsForm, self).__init__(*args, **kwargs)

    if self.instance and self.campaign:
      self.fields['recipients'] = forms.ModelMultipleChoiceField(
        queryset=Person.objects.filter(~Q(id__in=self.campaign.recipients.all())),
        widget=forms.widgets.CheckboxSelectMultiple,
        label='Recipients', help_text='Pick the recipients to add to the campaign',
        required=False,
      )
    elif self.campaign:
      self.fields['recipients'] = forms.ModelMultipleChoiceField(
        queryset=Person.objects.filter(~Q(id__in=self.campaign.recipients.all())),
        widget=forms.widgets.CheckboxSelectMultiple,
        label='Recipients', help_text='Pick the recipients to add to the campaign',
        required=False,
      )
    else:
      pass

  def save(self, force_insert=False, force_update=False, commit=True):
    recipients = self.cleaned_data['recipients']
    for person in recipients:
      recipient = Recipient(campaign=self.campaign,person=person)
      recipient.save()

  class Meta:
    model = Campaign
    fields = ['recipients',]

---

你能看看我的表单类并告诉我我做错了什么吗？当你使用旧的queryset（queryset=Person.objects.all（））时，我已经更新了问题内容。它是否显示了所有问题？另外，验证对self.campaign的访问，你可以执行一个简单的

引发异常（self.campaign.name）

就在

recipients=forms.modelmultipleechoicefield（）

我想知道self.campaign是否在类的主要部分不可见，可能是因为它在执行时没有初始化。如果是这种情况，您可能只需要在类中声明收件人，并使用方法根据self.campaign.Awesome初始化收件人列表，很高兴您已经弄明白了。

class RecipientsForm(forms.ModelForm):

  def __init__(self, *args, **kwargs):
    self.campaign = kwargs.pop('campaign', None)
    super(RecipientsForm, self).__init__(*args, **kwargs)

    if self.instance and self.campaign:
      self.fields['recipients'] = forms.ModelMultipleChoiceField(
        queryset=Person.objects.filter(~Q(id__in=self.campaign.recipients.all())),
        widget=forms.widgets.CheckboxSelectMultiple,
        label='Recipients', help_text='Pick the recipients to add to the campaign',
        required=False,
      )
    elif self.campaign:
      self.fields['recipients'] = forms.ModelMultipleChoiceField(
        queryset=Person.objects.filter(~Q(id__in=self.campaign.recipients.all())),
        widget=forms.widgets.CheckboxSelectMultiple,
        label='Recipients', help_text='Pick the recipients to add to the campaign',
        required=False,
      )
    else:
      pass

  def save(self, force_insert=False, force_update=False, commit=True):
    recipients = self.cleaned_data['recipients']
    for person in recipients:
      recipient = Recipient(campaign=self.campaign,person=person)
      recipient.save()

  class Meta:
    model = Campaign
    fields = ['recipients',]