1👍
You can use Ajax. This is other way to do it
base.html
<form method="POST" name="your_form" action="{% url 'your_app:your_url' %}">
<input type="text" name="vat" id="vat1" placeholder="Please Enter 10 digits number">
</form>
<script type="text/javascript">
$(document).ready(function(){
$('#vat1').keyup(function(event){
if (event.which == 13 || event.keyCode == 13){
if ($(this).val().length == 10){
$('your_form').submit();
}else{
// Show message if the text length is lesser than 10
}
}
});
});
</script>
Source:stackexchange.com