如果单单想达到楼主的目的
例如“113”转换成“壹壹叁”
这个就应该可以了吧?为什么要想那么复杂呢
    public static string NumberChange(string xiao)
        {
            string dealed=xiao;
            dealed=dealed.Replace ("1","壹");
            dealed=dealed.Replace ("2","贰");
            dealed=dealed.Replace ("3","叁");
            dealed=dealed.Replace ("4","肆");
            dealed=dealed.Replace ("5","伍");
            dealed=dealed.Replace ("6","陆");
            dealed=dealed.Replace ("7","柒");
            dealed=dealed.Replace ("8","捌");
            dealed=dealed.Replace ("9","玖");
            dealed=dealed.Replace ("0","零");
            return dealed;
        }
        public static string NumberChange(int xiao)
        {
            string dealed=xiao.ToString ();
            dealed=dealed.Replace ("1","壹");
            dealed=dealed.Replace ("2","贰");
            dealed=dealed.Replace ("3","叁");
            dealed=dealed.Replace ("4","肆");
            dealed=dealed.Replace ("5","伍");
            dealed=dealed.Replace ("6","陆");
            dealed=dealed.Replace ("7","柒");
            dealed=dealed.Replace ("8","捌");
            dealed=dealed.Replace ("9","玖");
            dealed=dealed.Replace ("0","零");
            return dealed;
        }