Memo的自动滚动

procedure TForm1.Edit1KeyDown(Sender: TObject; var Key: Word;
Shift: TShiftState);
begin
if Key = VK_F8 then
SendMessage(Memo1.Handle, { HWND of the Memo Control }
WM_VSCROLL, { Windows Message }
SB_PAGEDOWN, { Scroll Command }
0) { Not Used }
else if Key = VK_F7 then
SendMessage(Memo1.Handle, { HWND of the Memo Control }
WM_VSCROLL, { Windows Message }
SB_PAGEUP, { Scroll Command }
0); { Not Used }
end;