BitCoinClient.Program.HexStringToByteArray C# (CSharp) Method

        public static byte[] HexStringToByteArray(string hex)
        {
            if (hex.Length % 2 == 1)
                throw new Exception("The binary key cannot have an odd number of digits");

            byte[] arr = new byte[hex.Length >> 1];

            for (int i = 0; i < hex.Length >> 1; ++i)
            {
                arr[i] = (byte)((GetHexVal(hex[i << 1]) << 4) + (GetHexVal(hex[(i << 1) + 1])));
            }

            return arr;
        }

 public WorkBlock(JObject obj)
 {
     midstate = Program.HexStringToByteArray(obj["midstate"].ToString());
     data     = Program.HexStringToByteArray(obj["data"].ToString());
     hash1    = Program.HexStringToByteArray(obj["hash1"].ToString());
     target   = Program.HexStringToByteArray(obj["target"].ToString());
 }