Subscribe and unsubscribe from events

gistfile1.cs

public class Worker
    {
        public void StartWork()
        {
            for (var i = 0; i < 10; i++)
            {
                OnInterestingEvent();
                Thread.Sleep(1000);
            }
            OnComplete();
        }

        public event EventHandler Complete;
        public event EventHandler InterestingEvent;

        protected virtual void OnComplete()
        {
            EventHandler handler = Complete;
            if (handler != null) handler(this, EventArgs.Empty);
        }

        protected virtual void OnInterestingEvent()
        {
            EventHandler handler = InterestingEvent;
            if (handler != null) handler(this, EventArgs.Empty);
        }


    }

    public class TestEvents
    {
        public static void Main(string[] args)
        {
            _worker = new Worker();            
            _worker.InterestingEvent += HandleEvent;
            _worker.Complete += Complete;
            _worker.StartWork();

            while (!_complete)
            {
                Thread.Sleep(500);
            }
        }

        static void Complete(object sender, EventArgs e)
        {
            _complete = true;
        }

        private static void HandleEvent(object sender, EventArgs e)
        {
            _eventCount += 1;
            Console.WriteLine(_eventCount);
            if (_eventCount > 5)
            {
                _worker.InterestingEvent -= HandleEvent;
            }
        }

        private static Worker _worker = null;
        private static int _eventCount = 0;
        private static bool _complete = false;
    }