C# 16進制與字符串、字節數組之間的轉換

在串口通訊過程中，經常要用到 16進制與字符串、字節數組之間的轉換

        /// <summary>
        /// 字符串轉16進制字節數組
        /// </summary>
        /// <param name="hexString"></param>
        /// <returns></returns>
        private static byte[] strToToHexByte(string hexString)
        {
            hexString = hexString.Replace(" ", "");
            if ((hexString.Length % 2) != 0)
                hexString += " ";
            byte[] returnBytes = new byte[hexString.Length / 2];
            for (int i = 0; i < returnBytes.Length; i++)
                returnBytes[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16);
            return returnBytes;
        }

        /// <summary>
        /// 字節數組轉16進制字符串
        /// </summary>
        /// <param name="bytes"></param>
        /// <returns></returns>
        public static string byteToHexStr(byte[] bytes)
        {
            string returnStr = "";
            if (bytes != null)
            {
                for (int i = 0; i < bytes.Length; i++)
                {
                    returnStr += bytes[i].ToString("X2");
                }
            }
            return returnStr;
        }

        /// <summary>
        /// 從漢字轉換到16進制
        /// </summary>
        /// <param name="s"></param>
        /// <param name="charset">編碼,如"utf-8","gb2312"</param>
        /// <param name="fenge">是否每字符用逗號分隔</param>
        /// <returns></returns>
        public static string ToHex(string s, string charset, bool fenge)
        {
            if ((s.Length % 2) != 0)
            {
                s += " ";//空格
                //throw new ArgumentException("s is not valid chinese string!");
            }
            System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);
            byte[] bytes = chs.GetBytes(s);
            string str = "";
            for (int i = 0; i < bytes.Length; i++)
            {
                str += string.Format("{0:X}", bytes[i]);
                if (fenge && (i != bytes.Length - 1))
                {
                    str += string.Format("{0}", ",");
                }
            }
            return str.ToLower();
        }

        /// <summary>
        /// 從16進制轉換成漢字
        /// </summary>
        /// <param name="hex"></param>
        /// <param name="charset">編碼,如"utf-8","gb2312"</param>
        /// <returns></returns>
        public static string UnHex(string hex, string charset)
        {
            if (hex == null)
                throw new ArgumentNullException("hex");
            hex = hex.Replace(",", "");
            hex = hex.Replace("\n", "");
            hex = hex.Replace("\\", "");
            hex = hex.Replace(" ", "");
            if (hex.Length % 2 != 0)
            {
                hex += "20";//空格
            }
            // 需要將 hex 轉換成 byte 數組。 
            byte[] bytes = new byte[hex.Length / 2];

            for (int i = 0; i < bytes.Length; i++)
            {
                try
                {
                    // 每兩個字符是一個 byte。 
                    bytes[i] = byte.Parse(hex.Substring(i * 2, 2),
                    System.Globalization.NumberStyles.HexNumber);
                }
                catch
                {
                    // Rethrow an exception with custom message. 
                    throw new ArgumentException("hex is not a valid hex number!", "hex");
                }
            }
            System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);
            return chs.GetString(bytes);
        }