JSFiddle - React, Tailwind, and code Playground

by Serge Zahharenko

HTML

<select>
    <option value="1">Value1</option>
    <option value="2">Value2</option>
    <option value="3">Value3</option>
</select>

JavaScript

var oldValue = null;
$('select').click(function(){
  s = $(this);
  val = s.val();
  if (oldValue == null) {
      oldValue = val;
  } else {
      oldValue == s.val() ? alert('nothing changed') : alert('new value');
      $(document).unbind('click.valueCheck');
      oldValue = null;      
  }
})