Model Validation

I have a model M that has a field num=models.IntegerField()
I have a modelform called 'F' for model 'M'.
I want to ensure that num is never negative.

If I do validation in my form class, 'F', then i can do clean_num():
if negative than throw ValidationError('Num can never be negative').
This validationerror will be automatically redisplayed to the user by
redirecting him to back to the form that he submitted and displaying
the 'Num can never be negative' message on top of the num field.
Thats all done automatically by django as soon as I throw the
validationerror from the clean_fieldname method.

I would like to be able to do all that, but in the model class.

So F, that has a FormField for the ModelField 'num' , will fail and
display the error message defined in the model class that its
representing.
Also F2 and Fxxx will do the same if they all represent 'M' and have a
FormField for ModelField num.

How can I achieve this?

Thank you for your time and kind concern.
jenia

--
You received this message because you are subscribed to the Google Groups "Django users" group.
To post to this group, send email to django-users@googlegroups.com.
To unsubscribe from this group, send email to django-users+unsubscribe@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/django-users?hl=en.