从小数转换成中文金额大写，C#

#region 新大写转换函数
        private static char ToNum(char x)
        {
            string strChnNames="零壹贰叁肆伍陆柒捌玖";
            string strNumNames="0123456789";
            return strChnNames[strNumNames.IndexOf(x)];
        }
  
        // 转换万以下整数
        private static string ChangeInt(string x)
        {
            string[] strArrayLevelNames=new string[4] {"","拾","佰","仟"};
            string ret = "";
            int i;
            for (i=x.Length-1;i>=0;i--)
                if (x[i] == '0')
                    ret = ToNum(x[i]) + ret;
                else
                    ret = ToNum(x[i]) + strArrayLevelNames[x.Length-1-i] + ret;
            while ((i=ret.IndexOf("零零"))!=-1)
                ret=ret.Remove(i, 1);
            if (ret[ret.Length-1]=='零' && ret.Length>1)
                ret=ret.Remove(ret.Length-1,1);
            if (ret.Length>=2 && ret.Substring(0,2)=="一十")
                ret=ret.Remove(0,1);
            return ret;
        }

        // 转换整数
        private static string ToInt(string x)
        {
            int len = x.Length;
            string ret,temp;
            if (len<=4)
                ret = ChangeInt(x);
            else if (len<=8)
            {
                ret = ChangeInt(x.Substring(0,len-4)) + "万";
                temp = ChangeInt(x.Substring(len-4,4));
                if (temp.IndexOf("仟")==-1 && temp!="")
                    ret += "零" + temp;
                else
                    ret += temp;
            }
            else
            {
                ret=ChangeInt(x.Substring(0,len-8)) + "亿";
                temp=ChangeInt(x.Substring(len-8,4));
                if (temp.IndexOf("仟")==-1 && temp!="")
                    ret += "零" + temp;
                else
                    ret += temp;
                ret += "万";
                temp = ChangeInt(x.Substring(len-4,4));
                if (temp.IndexOf("仟")==-1 && temp!="")
                    ret += "零" + temp;
                else
                    ret += temp;
            }
            int i;
            if ((i=ret.IndexOf("零万"))!=-1)
                ret = ret.Remove(i+1,1);
            while ((i=ret.IndexOf("零零"))!=-1)
                ret = ret.Remove(i,1);
            if (ret[ret.Length-1]=='零' && ret.Length>1)
                ret = ret.Remove(ret.Length-1,1);
            return ret;
        }

        private static string ToDecimal(string x)
        {
            string ret = "";
            int i = 0;
            if (x != "00")
            {
                if (x.Substring(0,1) != "0")
                {
                    i = x[0] - 48; //Ascii
                    ret = ToNum(i.ToString()[0]) + "角" + ret;
                }
                else
                    ret = ToNum(i.ToString()[0]) + ret;

                if (x.Substring(1,1) != "0")
                {
                    i = x[1] - 48; //Ascii
                    ret = ret + ToNum(i.ToString()[0]) + "分";
                }
            }
            else
            {
                ret = "整";
            }
            return ret;
        }

        public static string MoneyLowerToUpper(decimal rmb)
        {
            string x = rmb.ToString();
            if (x.Length==0)
                return "";
            string ret="";
            if (x[0]=='-')
            {
                ret="负";
                x=x.Remove(0,1);
            }
            if (x[0].ToString()==".")
                x="0"+x;
            if (x[x.Length-1].ToString()==".")
                x=x.Remove(x.Length-1,1);
            if (x.IndexOf(".")>-1)
                ret += ToInt(x.Substring(0,x.IndexOf(".")))+"元"+ToDecimal(x.Substring(x.IndexOf(".")+1));
            else
                ret += ToInt(x);
            return ret;
        }

        #endregion