Destroying objects

Hi all,

In the book I read it says:

"The destructor should only release resources that your object holds on to, and should not reference other objects. Note that if you have only managed references, you don't need to and should not implement a destructor; you want this only for handling unmanaged resources. Because there is some cost to having a destructor, you ought to implement this only on methods that require it (that is, methods that consume valuable unmanaged resources)."

Does this mean, I shouldn't use destructors If so, say I have a static member storing the number of current instances, incremented by the constructor, how do I decrement it when an object is destroyed

Is there any other way around this

Thanks,

aw

Thanks guys. I am not sure how to do that. But I guess that's because of my c# knowledge.

Thanks,

aw

You don't have any control over when your C# destructor (finalizer) is called anyhow, so it's usefulness is almost nil. Also, the book you read should have said to implement IDisposable, create a Dispose method to get rid of your unmanaged resources.

E.g.:

private bool _disposed = false;

public Dispose()
{
Dispose(true);
GC.SuppresFinalize(this);
}

protected virtual void Dispose(bool disposing)
{
if (_disposed) return;

if (disposing)
// Do clean-up

_disposed = true;
}

You don't really need a finalizer. Additionally, if the clean-up stuff makes calling other methods invalid, use the _disposed member variable to determine if the object has disposed and throw ObjectDisposedException if so.

C# destructors (finalizers) are difficult to write because any reference you have may be invalid in the finalizer since the calls to finalizers is not guaranteed to be in any kind of order. Best to just avoid it and implement the dispose pattern.

Thanks Robert. Your example is almost exact to the book. Did you contribute to the book

Thanks,

aw