如何在Django中保存ManyToMany字段？

Question

我有模型是这样的：

class GuestStatus(models.Model): 
    guest_status = models.CharField(max_length=200) 
    arrangement = models.IntegerField(unique=True, help_text="Start from 1. Guest status will be arranged alphabetically.") 


class Guest(models.Model): 
    user = models.ForeignKey(User) 
    full_name = models.CharField(max_length=250) 
    status = models.ManyToManyField(GuestStatus, blank=True, null=True) 
    invitation_date = models.DateTimeField(blank=True, null=True) 

我想ManyToManyField被显示为复选框。这就是为什么我在做这样的：

class GuestForm(ModelForm): 
    status = forms.ModelMultipleChoiceField(queryset=GuestStatus.objects.all().order_by('arrangement'), widget=forms.CheckboxSelectMultiple, required=False) 
    class Meta: 
     model = Guest 
     exclude = ['user', 'invitation_date'] 

我试图保存表单是这样的：

form = GuestForm(request.POST) 
    if form.is_valid(): 
     status = form.cleaned_data['status'] 
     guest.status = status 
     if status: 
      invitation_date = datetime.now() 
     else: 
      invitation_date = None 
     new_guest = form.save(commit=False) 

     new_guest.user = request.user 
     new_guest.save() 
     new_guest.status = status 
     form.save_m2m() 

     return HttpResponseRedirect('/list_guests/') 

的形式保存所有的数据，但不能status值。哪里不对？另外，成功保存后，如何访问模板中的状态值？由于

Answer 1

我会做这样的：

form = GuestForm(request.POST) 
if form.is_valid(): 
    if status: 
     invitation_date = datetime.now() 
    else: 
     invitation_date = None 

    new_guest = form.save(commit=False) 
    new_guest.user = request.user 
    new_guest.save() 

    status = form.cleaned_data['status'] 
    for stat in status: 
     new_guest.status_set.create(guest_status = stat['guest_status'], arrangement = stat['arrangement']) 

    return HttpResponseRedirect('/list_guests/') 

后您得到您的new_guest实例创建GuestStatus实例并将其绑定到new_guest。

或者，如果GuestStatus是你的字典，您可以：

for stat in status: 
     gs = GuestStatus.objects.get(pk = stat['guest_status']) 
     new_guest.status_set.add(gs) 

希望你了解我和我的英语:)