Skrolovanie bez ScrollBar-ov – Delphi – Fórum – Programujte.com

Vsetkych zdravim.
Mam jednu prosbicku. Potrebujem v aplikaci skrolovat v hlavnej obrazovke, ale bez pouzitia primarnych - delfiackych ScrollBar-ov formulara, ktore samozrejme vypnem. Ako mam implementovat obsluhu udalosti FormKeyDown? Kde mam chybu viz. nizsie?

procedure TMainForm.FormKeyDown(Sender: TObject; var Key: Word;
Shift: TShiftState);
begin
case Key of
VK_UP:
begin
Perform(WM_VSCROLL, SB_LINEUP, 0);
Perform(WM_VSCROLL, SB_ENDSCROLL, 0);
end;
VK_LEFT:
begin
Perform(WM_HSCROLL, SB_LINELEFT, 0);
Perform(WM_HSCROLL, SB_ENDSCROLL, 0);
end;
VK_RIGHT:
begin
Perform(WM_HSCROLL, SB_LINERIGHT, 0);
Perform(WM_HSCROLL, SB_ENDSCROLL, 0);
end;
VK_DOWN:
begin
Perform(WM_VSCROLL, SB_LINEDOWN, 0);
Perform(WM_VSCROLL, SB_ENDSCROLL, 0);
end;
end;
end;