C#关于自动得问题

我写了个程序就是时间控制的,我想在3个时间段执行不同的程序,一个按钮点击后就让程序自动执行然后跳过时间以后程序自动关闭.部分代码如下
 public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();            
        }        //提交输入的时间与当前时间比再执行的程序
        private void btnStart_Click(object sender, EventArgs e)
        {
                TimerExample te = new TimerExample();
                te.Main();
        }        //这是个Timer 控件
        private void btnTimer_Click(object sender, EventArgs e)
        {
            //while (true)
            //{
                TimerExample te = new TimerExample();
                te.Main();
            //}
        }    }
  //执行自动时间控制类
    public class TimerExample
    {
        public void Main()
        {
                System.Threading.AutoResetEvent autoEvent = new System.Threading.AutoResetEvent(false);
                StatusChecker statusChecker = new StatusChecker(10);                // Create the delegate that invokes methods for the timer.
                System.Threading.TimerCallback timerDelegate =
                    new System.Threading.TimerCallback(statusChecker.CheckStatus);                // Create a timer that signals the delegate to invoke 
                // CheckStatus after one second, and every 1/4 second 
                // thereafter.                //Console.WriteLine("{0} Creating timer.\n",
                //    DateTime.Now.ToString("h:mm:ss.fff"));                //获取当前小时
                string hh = DateTime.Now.Hour.ToString();
                //获取当前分
                string mm = DateTime.Now.Minute.ToString();
                //获取当前选项
                // string choice = comboTime.Text;
                //判断是否相等
                if (hh + ":" + mm == "9:41")
                {
                    //这里执行程序
                    // MessageBox.Show(hh + ":" + mm); 
                    //这里是开启一个新的进程
                    Process.Start("http://www.yahoo.com.cn");
                    //continue;
                }
                else
                {
                    //break;
                }
                System.Threading.Timer stateTimer =
                        new System.Threading.Timer(timerDelegate, autoEvent, 1000, 250);                // When autoEvent signals, change the period to every 
                // 1/2 second.
                autoEvent.WaitOne(5000, false);
                stateTimer.Change(0, 500);                //Console.WriteLine("\nChanging period.\n");
                if (hh + ":" + mm == "9:43")
                {
                    //这里执行程序
                    //MessageBox.Show(hh + ":" + mm);
                    //这里是开启一个新的进程
                    Process.Start("http://www.you2home.com");
                    //continue;
                }
                else
                {
                    //break;
                }
                // When autoEvent signals the second time, dispose of 
                // the timer.
                autoEvent.WaitOne(5000, false);
                stateTimer.Dispose();
                //Console.WriteLine("\nDestroying timer.");                if (hh + ":" + mm == "10:01")
                {
                    //这里执行程序
                    //MessageBox.Show(hh + ":" + mm);
                    //这里是开启一个新的进程
                    
                    ProcessStartInfo psi = new ProcessStartInfo("http://www.baidu.com");
                    Process.Start(psi);                    Process p = new Process();                    psi=p.StartInfo;
                }
                else
                {
                    //break;
                }
        }    }    public class StatusChecker
    {
        int invokeCount, maxCount;        public StatusChecker(int count)
        {
            invokeCount = 0;
            maxCount = count;
        }        // This method is called by the timer delegate.
        public void CheckStatus(Object stateInfo)
        {
            System.Threading.AutoResetEvent autoEvent = (System.Threading.AutoResetEvent)stateInfo;
            
            //要执行的程序            //Console.WriteLine("{0} Checking status {1,2}.",
            //    DateTime.Now.ToString("h:mm:ss.fff"),
            (++invokeCount).ToString();//);            if (invokeCount == maxCount)
            {
                // Reset the counter and signal Main.
                invokeCount = 0;
                autoEvent.Set();
            }
        }
    }