這是前兩天課堂上的例子，提供了一個自定義WindowsFormsApplication的範例，主要包括如下的功能

1. 單一例項

2. 閃屏

3. 登陸視窗

4. 工作列圖示和選單

需要注意的是，WindowsFormsApplicationBase這個類是要新增Microsoft.VisualBisic.dll引用的

    class MyApplication : WindowsFormsApplicationBase
    {
        NotifyIcon taskBarIcon;
        public MyApplication(bool singleton)
            : base
 
(AuthenticationMode.ApplicationDefined)
        {
            //設定單例項
            this.IsSingleInstance = true;

            
            //新增工作列按鈕
            taskBarIcon = new NotifyIcon();
            taskBarIcon.Icon = Properties.Resources.Northwind;
            ContextMenuStrip contextMenu = new ContextMenuStrip();
            contextMenu.Items.Add(
                new
 
 ToolStripMenuItem(
                    "退出",
                    Properties.Resources.close,
                    (sender, eventArgs) =>
                    {
                        if (MessageBox.Show(
                            "你是否真的要退出?",
                            "確認",
                            MessageBoxButtons.YesNo,
                            MessageBoxIcon.Question,
                            MessageBoxDefaultButton.Button2)
                            == DialogResult.Yes)
                        {
                            Application.Exit();
                        }
                    }));
            contextMenu.Items.Add(
                new
 
 ToolStripMenuItem(
                    "幫助",
                    Properties.Resources.help,
                    (sender, eventArgs) =>
                    {
                        MessageBox.Show("幫助文件還在製作中");
                    }));

            taskBarIcon.ContextMenuStrip = contextMenu;
            taskBarIcon.ShowBalloonTip(2000, "歡迎", "歡迎使用該軟體", ToolTipIcon.Info);
            taskBarIcon.Visible = true;
        }

        public MyApplication() : this(true) { }

        protected override void OnCreateSplashScreen()
        {
            base.OnCreateSplashScreen();

            LoginForm login = new LoginForm();
            if (login.ShowDialog() != DialogResult.OK)
            {
                Environment.Exit(-1);//這裡不能用Application.Exit,因為當前是一個自定義的Application
            }

            this.MinimumSplashScreenDisplayTime = 2000;//最少顯示兩秒
            this.SplashScreen = new SplashForm();

        }




        protected override void OnShutdown()
        {
            base.OnShutdown();
            taskBarIcon.Dispose();

        }
        protected override void OnStartupNextInstance(StartupNextInstanceEventArgs eventArgs)
        {
            base.OnStartupNextInstance(eventArgs);
            eventArgs.BringToForeground = true;
        }



        protected override void OnCreateMainForm()
        {
            base.OnCreateMainForm();

            this.MainForm = new MainForm();
        }
    }