Is it necessary to dispose System.Timers.Timer if you use one in your application?

Roman Shumikhin picture Roman Shumikhin · Jan 24, 2009 · Viewed 39.6k times · Source

I am using System.Timers.Timer class in one of the classes in my application. I know that Timer class has Dispose method inherited from the parent Component class that implements IDisposable interface. Instances of the class below are created many times during my application lifecycle; each of them has an instance of Timer class that generates Elapsed events continuously during the class's lifecycle. Should I implement IDisposable interface in the class that uses Timer class to dispose the timer object? (I have seen code that doesn't do this at all). I am afraid that some unmanaged resources will not be freed if I use the class below like this:

SomeClass someClass = new SomeClass();
someClass.DoSomething();
someClass = null;

The class:

using System.Timers;

public class SomeClass
{
    private Timer m_timer;

    public SomeClass()
    {           
        m_timer = new Timer();
        m_timer.Interval = 1000;
        m_timer.Elapsed += new ElapsedEventHandler(m_timer_Elapsed);
        m_timer.AutoReset = false;
        m_timer.Start();                       
    }

    public void DoSomething()
    {

    }

    private void m_timer_Elapsed(object sender, ElapsedEventArgs e)
    {
        try
        {
            //Do some task
        }
        catch (Exception ex)
        {
            //Ignore
        }
        finally
        {
            if (m_timer != null)
            {
                //Restart the timer
                m_timer.Enabled = true;
            }
        }
    }
}

Answer

flesh picture flesh · Jan 24, 2009

Generally speaking you should always dispose of disposable resources. I certainly would be looking to in the case you outline above. If you implement IDisposable on the class that implements the timer you can then use the class in a using statement, meaning resources will be explicitly released when your class is disposed.