[c#.net] สอบถามเรื่องการแปลงตัวเลขเป็นตัวอักษรครับ

Function changenum(num As String) As String
   Dim i As Integer, max As Integer, r As String, n As String
   num = Trim(Str(Val(num)))
   max = Len(num)
   For i = 1 To max
      r = Choose(((max - i + 1) Mod 6) + 1, "แสน", "", "สิบ", "ร้อย", "พัน", "หมื่น")
      n = Choose(Mid(num, i, 1) + 1, "ศูนย์", "หนึ่ง", "สอง", "สาม", "สี่", "ห้า", "หก", "เจ็ด", "แปด", "เก้า")
      If r = "สิบ" And n = "หนึ่ง" Then n = ""
      If n = "หนึ่ง" And r = "" And max <> 1 Then n = "เอ็ด"
      If i = 1 And n = "เอ็ด" And max > 1 Then n = "หนึ่ง" 
      If r = "สิบ" And n = "สอง" Then n = "ยี่"
      If r = "" And max - i + 1 > 6 Then r = "ล้าน"
      If n <> "ศูนย์" Then
         changenum = changenum & n & r
      Else
          If r = "ล้าน" Then changenum = changenum & r
      End If
   Next
End Function

public static string ToWord(decimal PriceAmount)
        {
            try
            {
                return MoneyToWordBath(PriceAmount) + MoneyToWordStarg(PriceAmount);
            }
            catch
            {
                return string.Empty;
            }
        }

public static string MoneyToWordBath(decimal PriceAmount)
        {
            try
            {
                string Price = Math.Truncate(PriceAmount).ToString();
                int len = Price.Length;
                if (len > 13)
                {
                    MessageBox.Show("ไม่รองรับ !");
                    return "";
                }

                string Word = string.Empty;
                string m = string.Empty;
                string n = string.Empty;
                for (int i = 0; i < Price.Length; i++)
                {
                    n = string.Empty;
                    m = string.Empty;
                    
                    n = (ltxt().FindAll(p => p.Num == Price.ToArray()[i].ToString()).FirstOrDefault().Word);
                    if (Price.ToArray()[i].ToString() != "0")
                    {
                        m = (lMoney().FindAll(p => p.index == len.ToString()).FirstOrDefault().word ?? string.Empty);
                    }
                    //if (item.ToString() == "1" && len == 1 && Price.Length >= 2) { n = "เอ็ด"; }
                    if (Price.ToArray()[i].ToString() == "1" && len == 1 && Price.Length >= 2)
                    {
                        var index = Price.ToList()[i - 1];
                        n = "เอ็ด";
                        if (index.ToString() == "0")
                        {
                            n = "หนึ่ง";
                        }
                    }

                    if (Price.ToArray()[i].ToString() == "1" && len == 7 && Price.Length >= 8)
                    {
                        var index = Price.ToList()[i-1];
                        n = "เอ็ด";
                        if (index.ToString() == "0")
                        {
                            n = "หนึ่ง";
                        }
                    }

                    if (Price.ToArray()[i].ToString() == "1" && (len == 2 || len == 8)) { n = ""; }
                    if (Price.ToArray()[i].ToString() == "2" && (len == 2 || len == 8)) { n = "ยี่"; }

                    Word += (n + m); len--;
                }

                return Word == string.Empty ? "" : Word + "บาท";
            }
            catch (Exception)
            {
                return string.Empty;
            }           
        }
 public static string MoneyToWordStarg(decimal PriceAmount)
        {
            try
            {
                decimal dc = (PriceAmount - Math.Truncate(PriceAmount));
                if (!dc.ToString("n2").Contains('.')) { return string.Empty; }

                string Price = dc.ToString("n2").Split('.')[1];
                int len = Price.Length;
                if (len > 13)
                {
                    MessageBox.Show("ไม่รองรับ !");
                    return string.Empty;
                }
                string Word = string.Empty;
                string m = string.Empty;
                string n = string.Empty;
                foreach (var item in Price.ToArray())
                {
                    n = string.Empty;
                    m = string.Empty;

                    n = (ltxt().FindAll(p => p.Num == item.ToString()).FirstOrDefault().Word);
                    if (item.ToString() != "0")
                    {
                        m = (lMoney().FindAll(p => p.index == len.ToString()).FirstOrDefault().word ?? string.Empty);
                    }
                    if (item.ToString() == "1" && len == 1 && Price.Length >= 2) { n = "เอ็ด"; }
                    if (item.ToString() == "1" && (len == 2 || len == 8)) { n = ""; }
                    if (item.ToString() == "2" && (len == 2 || len == 8)) { n = "ยี่"; }

                    Word += (n + m);
                    len--;
                }
                return Word == string.Empty ? "ถ้วน" : Word + "สตางค์";
            }
            catch
            {

                return string.Empty;
            }
        }

        static List<NumberList> ltxt()
        {
            var txt = new List<NumberList>();
            txt.Add(new NumberList { Num = "1", Word = "หนึ่ง" });
            txt.Add(new NumberList { Num = "2", Word = "สอง" });
            txt.Add(new NumberList { Num = "3", Word = "สาม" });
            txt.Add(new NumberList { Num = "4", Word = "สี่" });
            txt.Add(new NumberList { Num = "5", Word = "ห้า" });
            txt.Add(new NumberList { Num = "6", Word = "หก" });
            txt.Add(new NumberList { Num = "7", Word = "เจ็ด" });
            txt.Add(new NumberList { Num = "8", Word = "แปด" });
            txt.Add(new NumberList { Num = "9", Word = "เก้า" });
            txt.Add(new NumberList { Num = "0", Word = "" });
            return txt;
        }

        static List<UnitList> lMoney()
        {
            var wmney = new List<UnitList>();
            wmney.Add(new UnitList { index = "1", word = "" });
            wmney.Add(new UnitList { index = "2", word = "สิบ" });
            wmney.Add(new UnitList { index = "3", word = "ร้อย" });
            wmney.Add(new UnitList { index = "4", word = "พัน" });
            wmney.Add(new UnitList { index = "5", word = "หมื่น" });
            wmney.Add(new UnitList { index = "6", word = "แสน" });
            wmney.Add(new UnitList { index = "7", word = "ล้าน" });
            wmney.Add(new UnitList { index = "8", word = "สิบ" });
            wmney.Add(new UnitList { index = "9", word = "ร้อย" });
            wmney.Add(new UnitList { index = "10", word = "พัน" });
            wmney.Add(new UnitList { index = "11", word = "หมื่น" });
            wmney.Add(new UnitList { index = "12", word = "แสน" });
            wmney.Add(new UnitList { index = "13", word = "ล้านล้าน" });
            return wmney;
        }

    }

    public class NumberList
    {
        public string Num { get; set; }
        public string Word { get; set; }
    }

    public class UnitList
    {
        public string index { get; set; }
        public string word { get; set; }
    }