JavaScript实现四舍五入的几种方法代码合集

javascript小数四舍五入多种方法实现

用Javascript取float型小数点后两位，例22.127456取成22.13,如何做？&nbsp
1.&nbsp最笨的办法&nbsp

function get() 
{ 
var s = 22.127456 + ""; 
var str = s.substring(0,s.indexOf(".") + 3); 
alert(str); 
} 

2.&nbsp正则表达式效果不错&nbsp

<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.&nbsp他就比较聪明了…..&nbsp

<script> 
var num=22.127456; 
alert( Math.round(num*100)/100); 
</script> 

4.会用新鲜东西的朋友。&nbsp

<script> 
var num=22.127456; 
alert( num.toFixed(2)); 
</script>