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POThread safe destructible event firing class in C#
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copied!<p>Recently, I was asked to implement a class as part of a selection process. I did the program as requested. However, I failed in the test. I am really curious to know what is wrong in my solution. Any help is much appreciated. The question and my solution are given below</p> <p>Question: </p> <p>Implement a thread safe class which fires an event every second from construction. There need to be a function for finding the seconds elapsed. This class has to implement IDisposable and any calls to seconds elapsed function after calling dispose should fail.</p> <p>My solution:</p> <pre><code>namespace TimeCounter { public delegate void SecondsElapsedHandler(object o, EventArgs e); /// <summary> /// Summary description for SecondCounter /// </summary> public class SecondCounter : IDisposable { private volatile int nSecondsElapsed; Timer myTimer; private readonly object EventLock = new object(); private SecondsElapsedHandler secondsHandler; public SecondCounter() { nSecondsElapsed = 0; myTimer = new Timer(); myTimer.Elapsed += new ElapsedEventHandler(OneSecondElapsed); myTimer.Interval = 1000; myTimer.AutoReset = false; myTimer.Start(); } public void OneSecondElapsed(object source, ElapsedEventArgs e) { try { SecondsElapsedHandler handlerCopy; lock (EventLock) { handlerCopy = secondsHandler; nSecondsElapsed++; } if (secondsHandler != null) { secondsHandler(this, e); } } catch (Exception exp) { Console.WriteLine("Exception thrown from SecondCounter OneSecondElapsed " + exp.Message); } finally { if (myTimer != null) { myTimer.Enabled = true; } } } public event SecondsElapsedHandler AnotherSecondElapsed { add { lock (EventLock) { secondsHandler += value; } } remove { lock (EventLock) { secondsHandler -= value; } } } public int SecondsElapsed() { if (this.IsDisposed) { throw new ObjectDisposedException("SecondCounter"); } return nSecondsElapsed; } private bool IsDisposed = false; public void Dispose() { Dispose(true); GC.SuppressFinalize(this); } private void Dispose(bool Disposing) { if (!IsDisposed) { if (Disposing) { } if (myTimer != null) { myTimer.Dispose(); } } secondsHandler = null; IsDisposed = true; } ~SecondCounter() { Dispose(false); } } } </code></pre>

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