给数字添加分隔逗号，3个一组：如下

C#

#region 把数字用逗号隔开(每三位为一组)
        public static string NumberStr(string number)
        {
            if (!string.IsNullOrEmpty(number))
                return Double.Parse(number).ToString("n");
            else
                return "";
        }
#endregion

 输入 123456.78

输出 123,456.78 

 

javascript

 

function formatNum(num){   
         if(!/^(\+|-)?(\d+)(\.\d+)?$/.test(num)){alert("wrong!"); return num;}
         var a = RegExp.$1, b = RegExp.$2, c = RegExp.$3;
         var re = new RegExp().compile("(\\d)(\\d{3})(,|$)");
         while(re.test(b)) b = b.replace(re, "$1,$2$3");
         return a +""+ b +""+ c;
}