JSFiddle - React, Tailwind, and code Playground

HTML

<input type='text' class='foo-class' data-classname="foo">
<input type='text' class='bar-class' data-classname="bar">

JavaScript

$(document).on('focusout', 'input', callme);

function callme(){
   console.log('hello ' + $(this).data('classname'));
}