I previously wrote about how to quickly convert a byte array to its hex representation and back again in C. Now I’ve converted the same source code to C#. Even though there is a built in method using String.Format, it is too slow.

  public static string ByteArrayToHexString(byte[] Bytes)
  {
	 StringBuilder Result;
	 string HexAlphabet = “0123456789ABCDEF”;

	 Result = new StringBuilder();

	 foreach (byte B in Bytes)
		{
		Result.Append(HexAlphabet[(int)(B >> 4)]);
		Result.Append(HexAlphabet[(int)(B & 0xF)]);
		}

	 return Result.ToString();
  }

  public static byte[] HexStringToByteArray(string Hex)
  {
	 byte[] Bytes;
	 int ByteLength;
	 string HexValue = “\x0\x1\x2\x3\x4\x5\x6\x7\x8\x9|||||||\xA\xB\xC\xD\xE\xF”;

	 ByteLength = Hex.Length / 2;
	 Bytes = new byte[ByteLength];

	 for (int x = 0, i = 0; i < Hex.Length; i += 2, x += 1)
		{
		Bytes[x]  = (byte)(HexValue[Char.ToUpper(Hex[i + 0]) - '0'] << 4);
		Bytes[x] |= (byte)(HexValue[Char.ToUpper(Hex[i + 1]) - '0']);
		}

	 return Bytes;
  }

This entry was posted on Thursday, June 26th, 2008 at 1:11 pm and is filed under C#, Programming. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.