id,summary,reporter,owner,description,type,status,component,version,severity,resolution,keywords,cc,stage,has_patch,needs_docs,needs_tests,needs_better_patch,easy,ui_ux 13763,Setting prefix on a ModelForm causes is_valid() to return False,Mark Tranchant,nobody,"Setting the prefix attribute on a ModelForm causes is_valid() to always return False. I can't find anything in the docs that refers to this behaviour. I am bundling multiple ModelForms into a single HTML form, so I'm using the prefix. On submission, I bind each of the ModelForms to their bit of the POST data to process them. If I set the prefix (in case validation fails and I need to re-display) *before* the call to is_valid(), that call always fails. Here's a quick test case using lightly-simplified versions of my real classes: {{{ class RptTField(models.Model): report = models.ForeignKey(Rpt) config = models.ForeignKey(RptCfgTField) text = models.TextField() class RptTForm(forms.ModelForm): class Meta: model = RptTField exclude = ('report','config') >>> from myproj.models import * >>> a = RptTForm({'text':'hello world'}) >>> a.prefix >>> a.is_valid() True >>> b = RptTForm({'text':'hello world'},prefix='abc') >>> b.prefix 'abc' >>> b.is_valid() False }}} This is using the latest SVN release, 13353.",,closed,Forms,dev,,invalid,modelform prefix validation is_valid,,Unreviewed,0,0,0,0,0,0