1👍
As following the previous comments, maybe like this;
1. forms.py
class AssignmentForm(forms.ModelForm):
# as following @Rohan, to make it optional.
content = forms.FileField(required=False)
class Meta:
model = Assignment
fields = ['content', 'other_val']
2. yourtemplate.html
<form method="post" enctype="multipart/form-data" action=".">
{% csrf_token %}
{{ form.as_p }}
<button type="submit">Save</button>
</form>
<script>
{% if not form.content.value %}
$('#id_content').attr({'required': 'required'});
{% endif %}
</script>
The field of
content
is under required only if havn’t value before…
Source:stackexchange.com