static SerialPort serialPort = new SerialPort("COM1", 9600, Parity.None, 8, StopBits.One); //定义一个串口类的串口变量

        #endregion Fields

        #region Methods

        static void Main(string[] args)
        {
            Menu menu = new Menu("串口通信示例");
            menu.AddCommand("status", new Function(ShowStatus));
            menu.AddCommand("switch", new Function(SwitchPort));
            menu.AddCommand("set", new Function(SetPort));
            menu.AddCommand("send", new Function(SendData));
            menu.Start();
        }
        internal static IEnumerable<IMenu> ToMenuList(this IEnumerable<IMenuItem> menuItems, string instructionalText, int maxAllowed = Menu.MaxOnScreen)
        {
            var source = menuItems.ToNumberedMenuItems(maxAllowed).ToList();
            var currentMenu = new Menu(instructionalText);
            foreach (var menuItem in source)
            {
                currentMenu.AddMenuItem(menuItem);

                if (menuItem.IsMore)
                {
                    yield return currentMenu;
                    currentMenu = new Menu(instructionalText);
                }
            }

            if (!source.Last().IsMore)
            {
                yield return currentMenu;
            }
        }