Benchmark Run Result for: toggle classname string vs array vs classList

HTML Preparation code:

<div id="foo" class="some other classname"></div>

Tests:

string
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.className += " bar"; element.className = element.className.slice(0, -4); }
array
var element = document.getElementById("foo"); var i = 1000; while (i--) { var items = element.className.split(' ') if (items.indexOf('bar') < 0) { items.push('bar'); element.className = items.join(' ') } items = element.className.split(' ') items.pop() element.className = items.join(' '); }
classList
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.classList.add("bar"); element.classList.remove("bar"); }