procedure TForm1.pnl1MouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
ReleaseCapture;
SendMessage(pnl1.Handle,wm_SysCommand,$F012,);//改变位置
//ReleaseCapture;
//SendMessage(pnl1.Handle,wm_SysCommand,$F008,0);//改变大小
end;
http://blog.csdn.net/diligentcatrich/article/details/7789861