procedure TForm1.WndProc(var nMsg: TMessage);

 var s:string;

     procedure setShow(AShow: Integer);

     begin

       case AShow of

         : Memo1.Lines.Add('无');

         : Memo1.Lines.Add('右');

         : Memo1.Lines.Add('左');

         : Memo1.Lines.Add('下');

         : Memo1.Lines.Add('上');

       end;

     end;

 begin

   inherited;

   if (nMsg.Msg  = WM_MOUSEMOVE) then

   begin

     if (nX < nMsg.LParamLo) then

       setShow()

     else if (nX > nMsg.LParamLo) then

       setShow()

     else if (nY < nMsg.LParamHi) then

       setShow()

     else if (nY > nMsg.LParamHi) then

       setShow()

     else

       setShow();

     nX := nMsg.LParamLo;

     nY := nMsg.LParamHi;

     Label1.Caption := '...';

   end;

 end;