Question

我正在尝试使用Django ModelForms来让教师安排每周与学生一起上课。但是，每当我从modelform中保存每周课程的新实例时，m2m关系（学生和教师）都不会被保存。

我在Django文档中看得非常广泛，并尝试了一切来解决这个问题，包括在save方法上设置commit = False，然后使用save_m2m方法。没有骰子。

这是我的代码

models.py

class WeeklyClass(models.Model):

    status = models.CharField(
        max_length=1,
        choices=STATUS_CHOICES,
        default="A")
    students = models.ManyToManyField(
        Profile,
        limit_choices_to=models.Q(is_teacher=False),
        related_name='student_weekly_classes',)
    teachers = models.ManyToManyField(
        Profile,
        limit_choices_to=models.Q(is_teacher=True),
        related_name='teacher_weekly_classes',)

    class Meta:
        verbose_name = 'Class'
        verbose_name_plural = 'Classes'
        ordering = ["-created"]

forms.py

class WeeklyClassForm(ModelForm):
    class Meta:
        model = WeeklyClass
        fields = [
            "status",
            "students",
            "teachers",
            "weekday",
            "duration_hours",
            "hour",
            "minute"]

views.py

@login_required
def new_weekly_class(request):
    if request.method == "POST":
        form = WeeklyClassForm(request.POST)

        if form.is_valid():
            form.save()
            return redirect(reverse(
                "weekly_class_list",
                kwargs={"username": request.user.username}))
    else:
        form = WeeklyClassForm()

    return render(
        request,
        "weekly_classes/new_weekly_class.html",
        {"form": form})

Answer 1

form.save()不直接保存多个实例，因此在保存form.save（）之后还调用form.save_m2m()来保存多个关系。

@login_required
def new_weekly_class(request):
    if request.method == "POST":
        form = WeeklyClassForm(request.POST, request.FILES)
        if form.is_valid():
            form.save()
            form.save_m2m()
            return redirect("weekly_class_list", kwargs={"username": request.user.username})
    else:
        form = WeeklyClassForm()
    template = "weekly_classes/new_weekly_class.html"
    context = {"form": form}
    return render(request, template, context)

供参考：https://docs.djangoproject.com/en/dev/topics/forms/modelforms/#the-save-method

使用m2m关系保存Django ModelForms的问题

1 个答案: