django-'NoneType'对象不可调用

Question

重定向到结果页面时出现此错误.是因为在重定向页面中,"POST.get"函数无法获取用户在重定向之前在表单中输入的内容吗？

views.py

class InputFormView(FormView):
    template_name = 'inputform.html'
    form_class = InputForm

    def get_success_url(self):
        return ''.join(
        [
            reverse('result'),
            '?company=',self.request.POST.get('company'),
            '&region=',self.request.POST.get('region')  <is there anything wrong here---?       
        ]
        )


class ReulstView(FormView):
    context_object_name = 'result_list'
    template_name = 'result_list.html'
    model = Result

    if form.is_valid():
        company = form.cleaned_data['company']
        region = form.cleaned_data['region']

        self.queryset=Result.objects.filter(region=region)

        return render(request, 'result_list.html', {'form': form})

    def get_context_data(self, **kwargs):
        context = super(ReulstView, self).get_context_data(**kwargs)
        context["sales"] = self.get_queryset().aggregate(Sum('sales'))

        context["company"] = self.request.POST.get("company")
        context["region"] = self.request.POST.get("region")

        return context

    def get_queryset(self):
        return Result.objects.all()

追溯:

File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\core\handlers\base.py" in get_response
  132.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\base.py" in view
  71.             return self.dispatch(request, *args, **kwargs)
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\base.py" in dispatch
  89.         return handler(request, *args, **kwargs)
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\edit.py" in get
  205.         form = self.get_form()
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\edit.py" in get_form
  74.         return form_class(**self.get_form_kwargs())

Exception Type: TypeError at /result_list/
Exception Value: 'NoneType' object is not callable

Inputform

class InputForm(forms.ModelForm):
    company=forms.CharField(widget=forms.TextInput, label="Company",error_messages={'required': 'Please enter the company name'},required=True)

    #region   This form can display correctly with drop down list
    iquery = Dupont.objects.values_list('region', flat=True).distinct()
    iquery_choices = [('', 'None')] + [(region,region)  for region in iquery]
    region = forms.ChoiceField(choices=iquery_choices)

对于相同的功能,我尝试了另一个代码,即使没有错误但无法显示表单数据,它显示为无.希望您能通过以下链接回答我的问题:

django-为什么重定向后,表单显示"无"

Answer 1

我认为这是您的问题:您正在使用FormView但尚未定义要使用的表单类.form_class在类上设置attr,或覆盖get_form_class方法:

class ReulstView(FormView):
    context_object_name = 'result_list'
    template_name = 'result_list.html'
    model = Result
    form_class = InputForm

此外,该form_valid方法将接收表单实例,您不需要手动实例化它:

def form_valid(self, form, **kwargs):
    form = InputForm(self.request.POST)  # <- remove this line
    if form.is_valid():
    ...