How to add classes to elements in JS

Question

How can I add a class to an element only using JavaScript?

Edit: Apparently I was unclear, I meant HTML element.

Answer 1

using pure JavaScript

given the element:
<div id="my-div"></div>

var myDiv = document.getElementById("my-div");

myDiv.classList.add("my-div-new-class");

demo
https://code.sololearn.com/WT2gG9uO5VLG/?ref=app

Answer 2

t's important to note that there are no classes in JavaScript. Functions can be used to somewhat simulate classes, but in general JavaScript is a class-less language. Everything is an object. And when it comes to inheritance, objects inherit from objects, not classes from classes as in the "class"-ical languages.

https://www.phpied.com/3-ways-to-define-a-javascript-class/

Answer 3

https://www.w3schools.com/tags/att_global_class.asp
The benefit of this is that you can have the same HTML element, but present it differently depending on its class or ID. In the CSS, a class selector is a name preceded by a full stop (“.”) and an ID selector is a name preceded by a hash character (“#”).

Answer 4

create your element without a class in html first
<p>hello</p>
#js
p=document.querySelector("p");
p.setAttribute("class","myclass");
As easy as pie

Answer 5

S.D sorry if I was unclear, I meant add a class to an HTML element