javascript 格式化数字串

　　在应用编程中,经常会用到要将一个数字串如金额、总数等，格式化成一个易读的数字串,有时会要用到javascript来实现这一过程，不妨参考如下函数：

　　function formatValue(srcStr)
        {       
            var arrStr = srcStr.toString().split('.');
            var numStr = arrStr[0];
            var floatStr = arrStr[1];
            var output = numStr;
            if (numStr.length > 3)
            {
                var mod = numStr.length % 3;
                output = (mod > 0 ? (numStr.substring(0,mod)) : '');
                for (i=0 ; i < Math.floor(numStr.length / 3); i++)
                {
                    if ((mod == 0) && (i == 0))
                        output += numStr.substring(mod+ 3 * i, mod + 3 * i + 3);
                    else
                        output+= ',' + numStr.substring(mod + 3 * i, mod + 3 * i + 3);
                }
            }
            return output +"." + floatStr
        }