NotifyIcon notifyIcon = null;
public Form1()
{
    InitializeComponent();
    notifyIcon = new NotifyIcon();
    // Initializing notifyIcon here...
    notifyIcon.BalloonTipClicked += new EventHandler(notifyIcon_BalloonTipClicked);
}

void notifyIcon_BalloonTipClicked(object sender,EventArgs e)
{
    // Operation you want...
}

我希望它满足你的需求……