Timer timer = new Timer();
        List<Button> btns;
        int i = 0;

        public Form2()
        {
            InitializeComponent();
           
            btns = new List<Button>();
            foreach (Control con in this.Controls)
            {
                if (con is Button)
                {
                    btns.Add(con as Button);
                }
            }
            i = btns.Count;
            timer.Interval = 5000;
            timer.Tick += new EventHandler(timer_Tick);
            timer.Start();
            
        }

        void timer_Tick(object sender, EventArgs e)
        {
            //throw new NotImplementedException();

            btns[i - 1].ForeColor = Color.Red;
            i--;
        }

------解决方案--------------------

源码已发