Events Delegates and how to consume them

[Zolfaghar]

I found the following code

public static class GCNotification
{
public static Action<Int32> s_gcDone = null;
public static event Action<Int32> GCDone
{
add
{
if (s_gcDone == null) { new GenObject(0); new GenObject(2); }
s_gcDone += value;
}
remove { s_gcDone -= value; }
}
private sealed class GenObject
{
private Int32 m_generation;
public GenObject(Int32 generation) { m_generation = generation; }
~GenObject()
{
if (GC.GetGeneration(this) >= m_generation)
{
Action<Int32> temp = Volatile.Read(ref s_gcDone);
if (temp != null) temp(m_generation);
}
if ((s_gcDone != null)
&& !AppDomain.CurrentDomain.IsFinalizingForUnload()
&& !Environment.HasShutdownStarted)
{
if (m_generation == 0) new GenObject(0);
else GC.ReRegisterForFinalize(this);
}
else { }
}
}
}

And I was told it would notify an event consumer class when a collection occurs. So, given that I am very inexperienced, I created the following class to consume the event:

internal sealed class GListener
{
public GListener()
{
GCNotification.GCDone += HandleNotice;
}
private static void HandleNotice(Int32 gen)
{
Console.WriteLine($"Gen {gen} was just collected");
}
}

Then I put the following in the Main()

public static void Main()
{
GListener Listner = new GListener();

Timer t = new Timer(TimerCallback, null, 0, 2000);
Console.ReadLine();
t = null;
}
private static void TimerCallback(Object o)
{
Console.WriteLine("In TimerCallback:"+DateTime.Now);
GC.Collect();

}

I get an output as follows:
In TimerCallback:1/13/2019 2:18:11 PM
Gen 0 was just collected
In TimerCallback:1/13/2019 2:18:13 PM
Gen 0 was just collected
Gen 2 was just collected
In TimerCallback:1/13/2019 2:18:15 PM
Gen 2 was just collected
Gen 0 was just collected
In TimerCallback:1/13/2019 2:18:17 PM
Gen 0 was just collected
Gen 2 was just collected

So it seems to work, but I like to validate with someone that I consumed the event correctly. Frankly I am a bit unsure about how it works. I followed the guides online on how to consume the event, but I feel I don't fully understand it. more experienced and ask if I can get additional information about the collection. Like maybe a list of object names or something.

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