procedure TForm2.Button1Click(Sender: TObject);
var
  p:Cardinal;
  newpt:TPoint;
begin  newpt:= ClientToScreen(Point(Button2.Left,Button2.Top)) ;
    p:= (newpt.Y shl 16) or newpt.X;  
     SendMessage(handle,Messages.WM_LBUTTONDOWN,0,p);//按下
     SendMessage(handle,Messages.WM_LBUTTONUP, 0,p);//抬起      end;end;为什么Button2没反映