创建后分配外键值（登录用户）

Question

我有一个使用CBV的createview

class StudentCreate(LoginRequiredMixin, CreateView):

    login_url = '/signin/'
    model = Student
    fields = ['first_name', 'last_name' ]
    success_url = '/dashboard/'

各自型号.py

class Class_teacher(models.Model):

    first_name = models.CharField(max_length=200)
    last_name = models.CharField(max_length=200)
    standard = models.IntegerField()
    division = models.CharField(max_length=1)
    subject = models.CharField(max_length=200)
    email = models.CharField(max_length=30)


class Student(models.Model):

    first_name = models.CharField(max_length=200)
    last_name = models.CharField(max_length=200)
    classteacher = models.ForeignKey('Class_teacher', on_delete=models.SET_NULL,blank=True, null=True )

webapp具有登录功能。当用户（classteacher）登录时，他们可以添加学生。我想要的是学生（模型表单）中的classteacher字段应该自动设置为user，即classteacher创建学生后应保存在数据库中。Classteacher模型用相应的必填字段更新

Answer 1

在here中查找可以重写的CreateView的各种方法

在本例中，您希望重写form_valid()方法，在保存新的Student时调用该方法

from django.shortcuts import get_object_or_404

def form_valid(self, form):
    self.object = form.save(commit=False)
    self.object.classteacher = get_object_or_404(Class_teacher, email=self.request.user.email)
    self.object.save()
    return super().form_valid(form)

Answer 2

您需要定义自己的form_valid()。 我假设老师和你的用户模型是一对一的关系

def form_valid(self, form):
    student = form.save(commit=False)
    #retrieve the current logged_in teacher, of course you have to be sure this view is only accesible for teachers (in dispatch for exemple)
    self.object.classteacher = self.request.user.teacher
    self.object.save()
    return super(StudentCreate, self).form_vaild(form)

#bonus the dispatch
def dispatch(self, request, *args, **kwargs):
        #get the loged in user
        if request.user.teacher:
            return super(StudentCreate, self).dispatch(request, *args, **kwargs)
        else:
            raise Http404