jQuery addClass example

Change class name on click in jQuery

by Arup Rakshit

HTML

<ul>
  <li>1</li>
  <li>2</li>
  <li>3</li>
</ul>

JavaScript

var $li = $("ul > li");
var $item = $li.filter(':last-child');

var result = Array.prototype.findIndex.call($li, (li) => {
  return $item.is($(li))
})

alert(result);