Django Form 实时从数据库中获取数据的操作方法

class UserType(models.Model):
 caption = models.CharField(max_length=32)

python manage.py makemigrations
python manage.py migrate

from app01 import models
class DBForm(DForms.Form):
 host = fields.CharField()
 host_type = fields.IntegerField(
  widget=widgets.Select(choices=[])
 )
 def __init__(self, *args, **kwargs):
  super(DBForm, self).__init__(*args, **kwargs)
  self.fields['host_type'].widget.choices = models.UserType.objects.all().values_list('id', 'caption') # 自定义构造方法，实时从数据库中获取数据

#views.py
def index(request):
 if request.method == "GET":
  nameform = NameModelForm()
  return render(request, "form/index.html",locals())
 if request.method == "POST":
  nameform = NameModelForm(request.POST)
  if nameform.is_valid():
   firstname = nameform.cleaned_data["firstname"] 
   secondname = nameform.cleaned_data["secondname"]
   a = Name(firstname = firstname,secondname = secondname)
   a.save()
   print(firstname+secondname)
   return HttpResponse("提交成功")
  else:
   error_msg = nameform.errors.as_json()
   print(error_msg)
   return HttpResponse(error_msg)