JSFiddle - React, Tailwind, and code Playground
HTML
<div id="test">My id becomes test1</div>
JavaScript
var currrentID = $("div").attr("id");
var someInt = 1;
$("div").attr("id", currrentID+someInt);
<div id="test">My id becomes test1</div>
var currrentID = $("div").attr("id");
var someInt = 1;
$("div").attr("id", currrentID+someInt);