How to add a class to a DOM element
TL;DR: Use the add() method on element.classList
When you have a DOM element reference you can add a new class to it by using the add
method:
element.classList.add('myclass')
You can remove a class using the remove
method:
element.classList.remove('myclass')
Implementation detail: classList
is not an array, but rather it is a collection of type DOMTokenList.
You can’t directly edit classList
because it’s a read-only property. You can however use its methods to change the element classes.
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