JSFiddle - React, Tailwind, and code Playground

HTML

<div id=12>12</div>
<div id=13>13</div>
<div id=14>14</div>

JavaScript

var clickHandler = function(e){
  alert(this.id);
}

var elements = document.getElementsByTagName('div'); // All divs

for(var i = 0; i<elements.length; i++){
  elements[i].onclick = clickHandler;
}