On the garbage collection stuff, the IDisposable pattern is meant to combat the fact that clean up in the .NET Framework is non-deterministic. A class implements IDisposable in order to make the clean up of unmanaged resources deterministic. The reason the the Dispose method calls SupressFinalize is because the Finalize call is one of the most expensive operations in the runtime, and since it is only used to clean up unmanaged resources, there is no need to call it if the user has already called Dispose.

Just my two cents.

The article was very interesting. However, when I tried to use it (since I am a student studying C#) I found that oTable was not defined and therefore I got an error. I would appreciate the correction for this.

Thank you,

Al

And GDI resources can be expensive, especially in a long running application.

See this article by Eric Gunnerson (former C# program manger at MS) for more information.

public void Dispose()
{
this.Dispose(true);
GC.SuppressFinalize(this);
}

It calls Dispose(true), which actually does the clean up, and then tells the garbage collector not to call the finalizer for this object since its resources have already been freed.

The finalizer for Pen is

~Pen()
{
this.Dispose(false);
}

So if you create a Pen object and don’t call Dispose(), the finalizer will call Dispose() for you when the object is garbage collected.

See http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconImplementingDisposeMethod.asp

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