django 1.3 表单验证使用干净的方法来检索getlist

Question

我有一个带有复选框的表单，该表单运行良好，在我看来，我可以使用 request.POST.getlist('list') 来检索值列表。

目前我正在尝试在 clean 方法中进行一些表单验证，当我尝试使用 self.cleaned_data['list'] 时，我得到了最后一个值。我无法检索项目列表。

知道我该怎么做吗？

forms.py

class SelectList_Form(forms.Form):
    list = forms.CharField(required=False)


    def clean(self):
        super(SelectList_Form, self).clean()
        cleaned_data = self.cleaned_data

        try:
            # TODO: list validation
            if cleaned_data['list'].__len__() is 0:
                raise forms.ValidationError(_('Must select at least one of the lists below'),)

            if cleaned_data['list'].__len__() > 1:
                try:
                    # In here when i print list it only shows me the last value. It doesn't show me the list of values when the box is checked
                    print cleaned_data['list']



                except Main.DoesNotExist:
                    raise Http404

        except forms.ValidationError:
            raise

class Posting_Wizard(FormWizard):

    def render_template(self, request, form, previous_fields, step, context=None):
        if step == 0:
            obj = MainI18n.objects.filter(main__is_active=True, language=request.LANGUAGE_CODE).\
                    exclude(main__parent=None).order_by('main__parent').select_related(depth=1)
            category_choices=dict(['%s,%s' % (i.main.slug, i.main.parent.slug), '%s - %s' % (i.main.parent,i.label)] for i in obj)

            form.fields['categories'] = forms.CharField(widget=forms.RadioSelect(choices=category_choices.items()))


    if step == 1:
        category = request.POST.get('0-categories')

        pobj  = Main.objects.filter(slug=category.split(',')[1], parent=None).get()
        cobj =  Main.objects.filter(slug=category.split(',')[0], parent=pobj.id).get()
        lobj =  ListI18n.objects.filter(list__is_active=True, language=request.LANGUAGE_CODE, list__main__slug=category.split(',')[0], list__main__parent=pobj.id).select_related()

        list_choices = dict([i.id, i.title] for i in lobj)

        if cobj.mainproperties.relation == 'M':
           # Here i generate the checkboxes
            form.fields['list']=forms.CharField(widget=forms.CheckboxSelectMultiple(choices=list_choices.items()),label="Pick the list",)
        else:
            form.fields['list']=forms.CharField(widget=forms.RadioSelect(choices=list_choices.items()),label="Pick the list",)


    return super(Posting_Wizard, self).render_template(request, form, previous_fields, step, context)


def done(self, request, form_list):
    return HttpResponseRedirect(reverse('accounts-registration-wizard-done'))

def get_template(self, step):
    return 'listing/post/wizard/wizard_%s.html' % step

Answer 1

首先，这里有一些基本的 Python 错误。几乎不需要访问双下划线函数——它们是内部实现细节。请始终使用普通的len() 函数。而且，永远不要使用is 进行比较：它是用于标识的，因此只能用于您知道具有相同标识的事物，这基本上只是意味着None。所以你的代码应该是：

if len(cleaned_data['list']) == 0:

等等

其次，我不明白你为什么认为list 中可能有不止一个“元素”。您已将其定义为 CharField，它是包含许多字符的单个字段。您的 len 正在测试输入该字段的字符数，而不是字段数，但是您认为您已经定义了它们。