notifyIcon怎样显示汽泡提示,该如何处理

notifyIcon怎样显示汽泡提示
notifyIcon1.Icon   =   "dfg.ico ";
                        notifyIcon1.BalloonTipText   =   "提示内容 ";
                        notifyIcon1.BalloonTipTitle   =   "提示标题 ";

怎么样才能显示出来啊，谢谢!

[解决办法]
this.notifyIcon1.ShowBalloonTip(1000);