class ThreadTimerDemo
    {
        static void Main(string[] args)
        {
            // Create an AutoResetEvent to signal the timeout threshold in the
            // timer callback has been reached.
            var autoEvent = new AutoResetEvent(false);

            var statusChecker = new StatusChecker(10);

            // Create a timer that invokes CheckStatus after one second, 
            // and every 1/4 second thereafter.
            Console.WriteLine("{0:h:mm:ss.fff} Creating timer.\n",
                              DateTime.Now);
            var stateTimer = new Timer(statusChecker.CheckStatus,
                                       autoEvent, 1000, 250);

            // When autoEvent signals, change the period to every half second.
            autoEvent.WaitOne();
            stateTimer.Change(0, 500);
            Console.WriteLine("\nChanging period to .5 seconds.\n");

            // When autoEvent signals the second time, dispose of the timer.
            autoEvent.WaitOne();
            stateTimer.Change(0, 1000);
            Console.WriteLine("\nChanging period to 1 seconds.\n");
            autoEvent.WaitOne();
            stateTimer.Dispose();
            Console.WriteLine("\nDestroying timer.");
            Console.ReadKey();
        }
        class StatusChecker
        {
            private int invokeCount;
            private int maxCount;

            public StatusChecker(int count)
            {
                invokeCount = 0;
                maxCount = count;
            }

            // This method is called by the timer delegate.
            public void CheckStatus(Object stateInfo)
            {
                AutoResetEvent autoEvent = (AutoResetEvent)stateInfo;
                Console.WriteLine("{0} Checking status {1,2}.",
                    DateTime.Now.ToString("h:mm:ss.fff"),
                    (++invokeCount).ToString());

                if (invokeCount == maxCount)
                {
                    // Reset the counter and signal the waiting thread.
                    invokeCount = 0;
                    autoEvent.Set();
                }
            }
        }
    }

// The example displays output like the following:
//       11:59:54.202 Creating timer.
//       
//       11:59:55.217 Checking status  1.
//       11:59:55.466 Checking status  2.
//       11:59:55.716 Checking status  3.
//       11:59:55.968 Checking status  4.
//       11:59:56.218 Checking status  5.
//       11:59:56.470 Checking status  6.
//       11:59:56.722 Checking status  7.
//       11:59:56.972 Checking status  8.
//       11:59:57.223 Checking status  9.
//       11:59:57.473 Checking status 10.
//       
//       Changing period to .5 seconds.
//       
//       11:59:57.474 Checking status  1.
//       11:59:57.976 Checking status  2.
//       11:59:58.476 Checking status  3.
//       11:59:58.977 Checking status  4.
//       11:59:59.477 Checking status  5.
//       11:59:59.977 Checking status  6.
//       12:00:00.478 Checking status  7.
//       12:00:00.980 Checking status  8.
//       12:00:01.481 Checking status  9.
//       12:00:01.981 Checking status 10.
//       
//       Destroying timer.