Edit fiddle - JSFiddle - React, Tailwind, and code Playground

JSFiddle - React, Tailwind, and code Playground

HTML

<div id="foo">Hey</div>

JavaScript

function addClass(element, myClass) {
   console.log(element.className.indexOf(myClass))
   if((" " + element.className + " ").indexOf(" " +myClass+" ") == -1)
       element.className += ' ' + myClass; 
}

addClass(foo,'Test1');
addClass(foo,'Test1');
addClass(foo, 'Tes');

console.log(foo)

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JSFiddle - React, Tailwind, and code Playground

HTML

JavaScript

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Join the 4+ million users, and keep the JSFiddle dream alive.

Ad-free

Use pre-released features

Fiddle collections

Private collections and fiddles

Console