Problem in django ChoiceField

Question

I have come across a problem when I submit an empty radio input. If I select a choice, the form functions fine; however, if I leave it blank, I get the following error --

MultiValueDictKeyError at / Key 'like' not found in <QueryDict:...

I've tried several solutions, including using a dict.get on the mentioned field 'like' and deleting the column in the database -- it seems to be a problem in the forms module.

Here is my code:

In forms.py --

from django import forms

class PictureForm(forms.Form):
    like = forms.ChoiceField(widget=forms.RadioSelect(), choices=(
                    [('yes','yes'), ('no','no'),]),)
    name = forms.CharField()
    email = forms.EmailField()
    message = forms.CharField(widget=forms.Textarea)

And in views.py

def index2(request):
    if request.method == 'POST':
        form = PictureForm(request.POST)
        if form.is_valid():
            cd = form.cleaned_data
            Picture.objects.create(like=cd['like'], name=cd['name'], email=cd['email'], message=cd['message'])
            return HttpResponseRedirect ('/thanks/')
    else:
        form = PictureForm()
return render_to_response('index2.html', {'form':form}, context_instance=RequestContext(request))

I would like to have it so there is obviously no error when the radio submitted blank -- and

1) how to allow a blank submission, and

2) how to prompt an error message.

In addition, the validations are not working on this form (I've done previous tutorials, and this is the first time the validations aren't automatically working).

Thank you.

i think the answers to this similar question will help you out : http://stackoverflow.com/q/5895588/1037459 — , Nov 09 '11 at 10:58

score 3 · Answer 1 · answered May 08 '11 at 03:46

What does your Picture model look like? Does your model have any restrictions on the uniqueness of multiple columns? It looks like you are using your form to create a model, did you read the doc on ModelForm?

Your form can be simplified to:

from django.forms import ModelForm

class PictureForm(ModelForm):
    like = forms.ChoiceField(widget=forms.RadioSelect(), choices=(
                [('yes','yes'), ('no','no'),]),)
    class Meta:
        model = Picture

In your view:

if form.is_valid():
    form.save()

score 3 · Accepted Answer · answered May 08 '11 at 17:18

Picture.objects.create(like=cd['like'], [...])

You are trying to access the cd dictionary with a key that doesn't exist, since the field has no value.

Try putting in an if/else statement:

if like in cd:
    Picture.objects.create(like=cd['like'], [...])

Also, it's not clear if you're using a ModelForm as Thierry suggested, but if so, you might need to add the parameters blank=True, null=True to your Model field creation, in order to allow for null values.

Problem in django ChoiceField

2 Answers2