Как сохранить содержимое TPaintBox в BMP

Code:

var

Bitmap: TBitmap;

Source: TRect;

Dest: TRect;

begin

Bitmap := TBitmap.Create;

try

   with Bitmap do

   begin

     Width := MyPaintBox.Width;

     Height := MyPaintBox.Height;

     Dest := Rect(0, 0, Width, Height);

   end;

   with MyPaintBox do

     Source := Rect(0, 0, Width, Height);

   Bitmap.Canvas.CopyRect(Dest, MyPaintBox.Canvas, Source);

   Bitmap.SaveToFile('MYFILE.BMP');

finally

   Bitmap.Free;

end;

end;