在工程實踐中，經常會將一些位元組資訊轉換為16進位制字串，以便傳遞和分享，比如加密金鑰資訊。在這裡提供一段轉化示例， 以供交流學習。

將16進位制字串轉化為 位元組流

        public static byte[] HexStringToBytes(string hexStr)
        {
            if (string.IsNullOrEmpty(hexStr))
            {
                return new byte[0];
            }

            if (hexStr.StartsWith("0x"))
            {
                hexStr = hexStr.Remove(0, 2);
            }

            var count = hexStr.Length;

            if (count % 2 == 1)
            {
                throw new ArgumentException("Invalid length of bytes:" + count);
            }

            var byteCount = count / 2;
            var result = new byte[byteCount];
            for (int ii = 0; ii < byteCount; ++ii)
            {
                var tempBytes = Byte.Parse(hexStr.Substring(2 * ii,  2), System.Globalization.NumberStyles.HexNumber);
                result[ii] = tempBytes;
            }

            return result;
        }
 

將位元組流轉化為16進位制字串

        public static string BytesTohexString(byte[] bytes)
        {
            if (bytes == null || bytes.Count() < 1)
            {
                return string.Empty;
            }

            var count = bytes.Count();

            var cache = new StringBuilder();
            cache.Append("0x");
            for (int ii = 0; ii < count; ++ii)
            {
                var tempHex = Convert.ToString(bytes[ii], 16).ToUpper();
                cache.Append(tempHex.Length == 1 ? "0" + tempHex : tempHex);
            }

            return cache.ToString();
        }