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copied!<blockquote> <p>...you’ll notice that managed resources are not handled if disposing is false. How/when are they handled?</p> </blockquote> <p>You didn't include it in your sample, but often the type will have a destructor which will call <code>Dispose(false)</code>. Thus, when <code>disposing</code> is <code>false</code>, you "know" that you're in a finalizer call, and thus <em>should</em> *not* access any managed resources, <em>because</em> they might have <em>already</em> been finalized.</p> <p>The GC finalization process only ensures that finalizers are invoked, not the <em>order</em> that they're invoked in.</p> <blockquote> <p>what does the GG.SuppressFinalize(this) call do?</p> </blockquote> <p>It prevents the GC from adding your object to the finalization queue and eventually calling <code>object.Finalize()</code> (i.e. your destructor). It's a performance optimization, nothing more.</p> <blockquote> <p>The way the pattern is written, it seems they would get disposed (later) if you did nothing in the “if (disposing)” section</p> </blockquote> <p><em>Maybe</em>; it depends upon how the type is written. A major point to the <code>IDisposable</code> idiom is for "deterministic finalizaion" -- saying "I want your resources freed <em>now</em>" and having it mean something. If you "ignore" the <code>disposing=true</code> block and don't "forward" the <code>Dispose()</code> call, one of two things will happen:</p> <ol> <li>If the type has a finalizer, the finalizer for the object may eventually be invoked sometime "later".</li> <li>If the type doesn't have a finalizer, the managed resource will "leak," as <code>Dispose()</code> will never be invoked on them.</li> </ol> <blockquote> <p>it's important that you never acquire locks or use locking during your unmanaged cleanup.” Why is that? Does it apply to unmanaged resources as well?</p> </blockquote> <p>It's a sanity issue -- YOUR sanity. The simpler your cleanup code, the better, and it's <em>always</em> a good idea to <em>not</em> throw exceptions from <code>Dispose()</code>. Using locks can result in exceptions or deadlocks, either of which are good ways to ruin your day. :-)</p> <blockquote> <p>does on ever implement a finalizer (~MyClass() in C#) without implementing IDisposable</p> </blockquote> <p>One could, but it would be considered bad style.</p>

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