[NumLock]

Код:

var
  bmp: TBitmap;
  hWnd: THandle;
  dc: HDC;
begin
  hWnd:=GetForegroundWindow;
  dc:=GetDC(hWnd);
  bmp:=TBitmap.Create;
  bmp.Width:=100;
  bmp.Height:=100;
  try
    BitBlt(bmp.Canvas.Handle, 0, 0, 100, 100, dc, 0, 0, SRCCOPY);
    // work with bmp:
    Canvas.Draw(0, 0, bmp); // пример work
    bmp.ScanLine[0]; // пример 2 work
  finally
    bmp.Free;
    ReleaseDC(hWnd, dc);
  end;
end;