ขอทราบวิธี upload file ภาษาไทยไปยัง server window form

private string ConvertAsciiToUnicode(string theAsciiString)
        {
            // Create two different encodings. 
            Encoding aAsciiEncoding = Encoding.ASCII;
            Encoding aUnicodeEncoding = Encoding.UTF8;
            // Convert the string into a byte[]. 
            byte[] aAsciiBytes = aAsciiEncoding.GetBytes(theAsciiString);
            // Perform the conversion from one encoding to the other. 
            byte[] aUnicodeBytes = Encoding.Convert(aAsciiEncoding, aUnicodeEncoding,
            aAsciiBytes);
            // Convert the new byte[] into a char[] and then into a string. 
            char[] aUnicodeChars = new
            char[aUnicodeEncoding.GetCharCount(aUnicodeBytes, 0, aUnicodeBytes.Length)];
            aUnicodeEncoding.GetChars(aUnicodeBytes, 0, aUnicodeBytes.Length,
            aUnicodeChars, 0);
            string aUnicodeString = new string(aUnicodeChars);
            return aUnicodeString;
        } 

        private void ReadDataFromClient(object clientObject)
        {
            Socket clientSock = null;
            BinaryWriter bWriter = null;
            string fileName = "";
            try
            {
                SyncSocketServerMulClient.status = "";
                SyncSocketServerMulClient.presentOperation = "";
                clientSock = (Socket)clientObject;
                bool flag = true;
                Console.WriteLine("New connection estublished. Socket {0}", clientSock.GetHashCode());
                int totalDataLen, receivedLen, fileNameLen, fileContentStartIndex;
                byte[] data = new byte[bufferSize];
                currentStatus = presentOperation = "Data Receiving";
                int len = clientSock.Receive(data);
                if (len == 0)
                {
                    clientSock.Close();
                    return;
                }
                if (len == 3)
                {
                    string clientData = Encoding.UTF8.GetString(data);
                    if (clientData.Substring(0, len) == "END")
                        return;
                }
                totalDataLen = BitConverter.ToInt32(data, 0);
                fileNameLen = BitConverter.ToInt32(data, 4);

                Encoding aUnicodeEncoding = Encoding.UTF8;

                char[] aUnicodeChars = new char[aUnicodeEncoding.GetCharCount(data, 8, fileNameLen)];

                aUnicodeEncoding.GetChars(data, 8, fileNameLen, aUnicodeChars, 0);
                string aUnicodeString = new string(aUnicodeChars);
                string s = Encoding.UTF7.GetString(data, 8, fileNameLen);
                fileName = aUnicodeString;
                fileContentStartIndex = 4 + 4 + fileNameLen;
                receivedLen = len - fileContentStartIndex;
                //READ DATA & STORE OF FIRST PACKET