js 四舍五入保留二位小数

1. 最笨的办法....... [我就怎么干的.........]function get(){    var s = 22.127456 + "";    var str = s.substring(0,s.indexOf(".") + 3);    alert(str);}2. 正则表达式效果不错<script type="text/javascript">onload = function(){    var a = "23.456322";    var aNew;    var re = /([0-9]+\.[0-9]{2})[0-9]*/;    aNew = a.replace(re,"$1");    alert(aNew);}</script>3. 他就比较聪明了.....<script>var num=22.127456;alert( Math.round(num*100)/100);</script>4.会用新鲜东西的朋友....... 但是需要 IE5.5+才支持。<script>var num=22.127456;alert( num.toFixed(2));</script>三、总结后，自己写了个javascript多位数四舍五入的通用方法//num表示要四舍五入的数,v表示要保留的小数位数。function decimal(num,v){    var vv = Math.pow(10,v);    return Math.round(num*vv)/vv;}