asp.net 日期转换为大写汉字

//年份转换为大写汉字
        public static string numtoUpper(int num)
         {
             return "零壹贰叁肆伍陆柒捌玖"[num].ToString();
         }

//月份转换大写汉字
        public static string monthtoUpper(int month)
        {
            if (month < )
            {
                return numtoUpper(month);
            }
            else
            {
                if (month == ) { return "壹拾"; }

                else
                {
                    return "壹拾" + numtoUpper(month - );
                }
            }
        }

//日期转化为大写汉字
        public static string daytoUpper(int day)
        {
            if (day < )
            {
                return monthtoUpper(day);
            }
            else
            {
                String str = day.ToString();
                if (str[] == '')
                {
                    return numtoUpper(Convert.ToInt16(str[].ToString())) + "拾";
                }
                else
                {
                    return numtoUpper(Convert.ToInt16(str[].ToString())) + "拾"
                        + numtoUpper(Convert.ToInt16(str[].ToString()));
                }
            }
        }

static void Main(string[] args)
        {
            string year = "";
            string retur = string.Empty;
            for (int i = ; i < year.Length; i++)
            {
                retur += numtoUpper(int.Parse(year[i].ToString())).ToString();
            }
            Console.WriteLine(retur + "  年");
            retur = string.Empty;
            string month = "";
            retur = monthtoUpper(Convert.ToInt32(month));
            Console.WriteLine(retur + "  月");
            string day = "";
            retur = daytoUpper(Convert.ToInt32(day));
            Console.WriteLine(retur + "  日");
            Console.ReadLine();
        }