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Django: How do I add arbitrary html attributes to input fields on a form?

python
django
forms
widget-tweaks
Anton ShumikhinbyAnton Shumikhin·Oct 28, 2024
TLDR

Here's the quick fix for what you're looking for—adding custom HTML attributes to Django form inputs:

class MyForm(forms.Form): # Calling in Mr. CharField! my_field = forms.CharField() # Dr. __init__, I presume? def __init__(self, *args, **kwargs): # Commencing superpower activation! super().__init__(*args, **kwargs) # Time for some magic dust sprinkle...✨ self.fields['my_field'].widget.attrs['data-custom'] = 'value'

Now, my_field will appear onstage donning a data-custom="value" badge.

Widget attributes customization 101

Attributes are to form fields what sprinkles are to donuts—an extra touch that just makes everything better. Need to add a class or onclick event? Or maybe disable an annoying autocomplete? Here's how you can do it.

To add a class (or a fancy new outfit!) to our field:

# New identity loading... self.fields['my_field'].widget.attrs.update({'class': 'my-css-class'})

To turn off autocomplete (the autocomplete ghost bothering you):

# Ghostbusting time... self.fields['my_field'].widget.attrs.update({'autocomplete': 'off'})

And here's how you make your attributes dynamic:

# Time for a little fairy tale... if some_condition: self.fields['my_field'].widget.attrs['data-condition'] = 'true' # And they lived happily ever after. else: self.fields['my_field'].widget.attrs['data-condition'] = 'false' # Then came the dragon... 🐉

Manipulating model forms

Now, if you're trying to charm a ModelForm, you can go ahead and declare widgets in the Meta class:

class MyModelForm(forms.ModelForm): class Meta: model = MyModel fields = ['my_field'] widgets = { 'my_field': forms.TextInput(attrs={'autocomplete': 'off', 'class': 'my-class'}) }

This will let your my_field strut on the runway with an autocomplete="off" and class="my-class" sash.

Time for some magic: django-widget-tweaks

django-widget-tweaks can be your magical wand for setting attributes within your templates:

{% load widget_tweaks %} {# Reverse spell casting in 3...2..1..! #} {{ form.my_field|add_class:"my-css-class" }} {{ form.my_field|attr:"data-custom:value" }}

Common hiccups (and how to avoid them)

While you're busy immersing in the wizardry of form fields' HTML attributes, be sure to ward off these common demons:

  • The attribute eraser: Always use .update() or risk wiping out all other attributes.
  • The class collision: Ensure a new class won't clash with others. Remember, balance is key.
  • The browser ghost: Some browsers cache forms—your changes might be invisible unless the cache is cleared.