Django 如何在queryset中添加默认值？

我有一本记事本，一本记事本

而moneylog与moneybook有着千丝万缕的联系

moneybook = models.ForeignKey(
    moneybook_models.Moneybook, on_delete=models.CASCADE)
pay_day = models.DateTimeField(default=NOW)
payer = models.ForeignKey(
    user_models.User, on_delete=models.CASCADE, related_name="payer")
dutch_payer = models.ManyToManyField(
    user_models.User, related_name="dutch_payer", blank=True)
price = models.IntegerField()
category = models.CharField(max_length=10)
memo = models.TextField()

如果用户选择或不选择，我希望付款人以荷兰语保存默认付款人

这是我的表单.py

class CreateMoneylogForm(forms.ModelForm):
    class Meta:
        model = models.Moneylog
        fields = (
            "pay_day",
            "payer",
            "dutch_payer",
            "price",
            "category",
            "memo",
        )
        widgets = {
            "dutch_payer": forms.CheckboxSelectMultiple
        }

    def save(self, *args, **kwargs):
        moneylog = super().save(commit=False)
        return moneylog

class moneylog_create(FormView):

    form_class = forms.CreateMoneylogForm
    template_name = "moneylogs/create.html"

    def form_valid(self, form):
        moneylog = form.save()
        moneybook = moneybook_models.Moneybook.objects.get(
            pk=self.kwargs["pk"])
        form.instance.moneybook = moneybook
        if moneylog.payer not in moneylog.dutch_payer.all():
            moneylog.dutch_payer.add(moneylog.payer)
        moneylog.save()
        form.save_m2m()
        return redirect(reverse("cores:home"))

视图.py

class CreateMoneylogForm(forms.ModelForm):
    class Meta:
        model = models.Moneylog
        fields = (
            "pay_day",
            "payer",
            "dutch_payer",
            "price",
            "category",
            "memo",
        )
        widgets = {
            "dutch_payer": forms.CheckboxSelectMultiple
        }

    def save(self, *args, **kwargs):
        moneylog = super().save(commit=False)
        return moneylog

class moneylog_create(FormView):

    form_class = forms.CreateMoneylogForm
    template_name = "moneylogs/create.html"

    def form_valid(self, form):
        moneylog = form.save()
        moneybook = moneybook_models.Moneybook.objects.get(
            pk=self.kwargs["pk"])
        form.instance.moneybook = moneybook
        if moneylog.payer not in moneylog.dutch_payer.all():
            moneylog.dutch_payer.add(moneylog.payer)
        moneylog.save()
        form.save_m2m()
        return redirect(reverse("cores:home"))

如你所见

    if moneylog.payer not in moneylog.dutch_payer.all():
        moneylog.dutch_payer.add(moneylog.payer)
    moneylog.save()
    form.save_m2m()
    return redirect(reverse("cores:home"))

---

这不起作用。（荷兰语中没有付款人）我如何才能实现它？

这是否回答了您的问题？谢谢您的回复，但是保存是有效的，但是moneylog.dutch\u payer.add（moneylog.payer）不起作用。我尝试了save_m2m，但也不起作用。