javascript保留两位

        //保留两位小数     
        //功能：将浮点数四舍五入，取小数点后2位    
        function toDecimal(x) {    
            var f = parseFloat(x);    
            if (isNaN(f)) {    
                return;    
            }    
            f = Math.round(x*100)/100;    
            return f;    
        }    

        //制保留2位小数，如：2，会在2后面补上00.即2.00    
        function toDecimal2(x) {    
            var f = parseFloat(x);    
            if (isNaN(f)) {    
                return false;    
            }    
            var f = Math.round(x*100)/100;    
            var s = f.toString();    
            var rs = s.indexOf(‘.‘);    
            if (rs < 0) {    
                rs = s.length;    
                s += ‘.‘;    
            }    
            while (s.length <= rs + 2) {    
                s += ‘0‘;    
            }    
            return s;    
        }