JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
  <li>
    <div id="mydiv1">index 1</div>
  </li>
  <li>
    <div id="mydiv2">index 2</div>
  </li>
</ul>

JavaScript

$(document).ready(function() {
  $("ul").on("click", "div", function() {
    var index = $("div").index(0);
    alert("Index: " + index);
  });
});