<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<div id="aa">12.00</div>
<div id="bb">12.666</div>
</body>
</html>
<script type="text/javascript">
// 取整
alert(Math.ceil(document.getElementById("aa").innerHTML));
// 保留两位小数
alert(Math.round(document.getElementById("bb").innerHTML * 100) / 100);
</script>