System.Net.NetworkInformation.StringParsingHelpers.HexToByte C# (CSharp) Method

        private static byte HexToByte(char val)
        {
            if (val <= '9' && val >= '0')
            {
                return (byte)(val - '0');
            }
            else if (val >= 'a' && val <= 'f')
            {
                return (byte)((val - 'a') + 10);
            }
            else if (val >= 'A' && val <= 'F')
            {
                return (byte)((val - 'A') + 10);
            }
            else
            {
                throw ExceptionHelper.CreateForParseFailure();
            }
        }
    }