Caps e num lock

Procedure TMyForm.Button1Click(Sender: TObject);
Var
KeyState : TKeyboardState;
begin
GetKeyboardState(KeyState);
if (KeyState[VK_NUMLOCK] = 0) then KeyState[VK_NUMLOCK] := 1
else KeyState[VK_NUMLOCK] := 0;
SetKeyboardState(KeyState);
End;

//Para a tecla Caps Lock basta trocar VK_NUMLOCK por VK_CAPITAL.