XColor SetGray Function. Set the color to a grayscale value. ABCpdf .NET PDF Library. From ABCpdf .net previous page next page SetGray Function Set the color to a grayscale value. Syntax [C#] void SetGray(int gray) void SetGray(int gray, int alpha) [Visual Basic] Sub SetGray(gray As Integer) Sub SetGray(gray As Integer, alpha as Integer) Params Name Description gray The amount of black (0 to 255). alpha The level of opacity from transparent through to fully opaque (0 to 255). Notes Set the color to grayscale and provide a value for it. Optionally set the alpha value to specify a transparency level. If this parameter is omitted the color is set to fully opaque - no transparency. Example None. previous page start next page