问题描述：
<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8">
<title>柴婷的测试</title>
<style>
.a{
color:red;
}
.b{
font-size: 45px;
}
</style>
</head>
<body>
<div class="a b">
我是div元素
</div>
<script type="text/javascript">
var node = document.getElementsByTagName('div')[0];
var cls = 'a';
var className = removeClass(node, cls);
node.setAttribute('class', className)
function removeClass(node, cls) {
var classList = node.getAttribute('class').split('');
for (let i = 0; i < classList.length; i++) {
if (classList[i] == cls) {
classList[i] = '';
}
}
classList = classList.join('');
return classList;
}
</script>
</body>
</html>
屏幕快照 2018-09-06 下午3.31.51.png
