How can I handle validation errors in Django model forms?

How can I handle validation errors in Django model forms?

In Django, you can handle validation errors in model forms by overriding the clean() method or using field-specific validation methods.

Can you give me an example of overriding the clean method?

Sure! You can override the clean() method like this:

class MyForm(forms.ModelForm):
    def clean(self):
        cleaned_data = super().clean()
        field_value = cleaned_data.get('field_name')
        if not field_value:
            raise forms.ValidationError('This field cannot be empty.')
        return cleaned_data

What about displaying these errors in the template?

You can display validation errors in your template using the {{ form.non_field_errors }} and {{ form.field_name.errors }} syntax to show specific field errors.

Is there a way to customize the error messages?

Yes, you can customize error messages by passing a error_messages dictionary in your field definition, like this:

field_name = forms.CharField(error_messages={'required': 'This field is required.'})