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    <p><strong>Questions 1 and 2</strong>: The CLR basically checks whether or not the finalizer is overridden. If it's not, it treats it as not having a finalizer.</p> <p>The benefit of having a finalizer in System.Object is that compilers know they can <em>always</em> put a call to <code>base.Finalize()</code> in. This avoids versioning issues. Consider a world without <code>System.Object.Finalize()</code>:</p> <ul> <li>System.Object (no Finalize)</li> <li>Acme.BaseClass (no Finalize)</li> <li>MyCompany.DerivedClass (Finalize)</li> </ul> <p>Without a <code>Finalize</code> method in object, the finalizer in MyCompany.DerivedClass can't call anything. Which leads to a problem when version 2 of Acme.BaseClass comes out <em>with</em> a finalizer. Unless you recompile MyCompany.DerivedClass, an instance of DerivedClass will be finalized without calling BaseClass.Finalize, which is clearly a Bad Thing.</p> <p>Now consider the same situation <em>with</em> System.Object.Finalize - the compiler inserts a call to base.Finalize automatically in DerivedClass.Finalize, which in version 1 just calls the no-op implementation in System.Object. When version 2 of Acme.BaseClass comes out, the call to <code>base.Finalize</code> will (without recompilation of DerivedClass) call BaseClass.Finalize.</p> <p><strong>Question 3</strong>: No, you don't need to have a finalizer just because you implement IDisposable. Finalizers should only be used for unmanaged resources which <em>nothing else is going to clean up</em> - i.e. ones you have a <em>direct</em> reference to. For instance, suppose you have a class which has a <code>FileStream</code> member variable. You want to implement <code>IDisposable</code> so you can close the stream as soon as possible, if the caller remembers - but if they <em>don't</em> remember to call <code>Dispose()</code>, the stream will become eligible for garbage collection at the same time as your object. Trust that <code>FileStream</code> has an appropriate finalizer (or a reference to something else with a finalizer etc) rather than trying to clean it up in your own finalizer.</p> <p>As of .NET 2.0, with the <a href="http://msdn.microsoft.com/en-us/library/system.runtime.interopservices.safehandle.aspx" rel="noreferrer">SafeHandle</a> class, it should be <em>incredibly</em> rare for you to need your own finalizer.</p>
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    1. COAm I correct in assuming that there is no need to call the GC.SuppressFinalize(this) in the IDisposable.Dispose() method in ManagedResourceHolder class (as it really has no finalizer to suppress) ?
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    2. COYup. No need to suppress what doesn't exist.
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    3. COUsing a finalizer anywhere other than a base-level class which is either sealed or designed for finalization seems dodgy to me, unless the sole purpose of the finalizer is to warn about a failure to properly dispose an object. If an object needs to ensure that something gets cleaned up when it goes out of scope, it should encapsulate the information and impetus necessary to conduct such cleanup into a small dedicated class. Only that small class will then have to be kept alive during finalization.
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