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    <p>Yes, if your <code>ClassB</code> has a reference to a <code>ClassC</code> instance via <code>objCStrongRef</code>, then if the <code>ClassB</code> is still alive you don't need to worry about <code>the ClassC</code> evaporating at random. The exception to this is if you write a finalizer, i.e.</p> <pre><code>~ClassB() { ...} </code></pre> <p>In <em>there</em>, you <strong>should not</strong> attempt to talk to <code>objCStrongRef</code> <em>at all</em>; because you can have no clue which object gets finalized first. If <code>ClassC</code> needs something at finalization, it should have a separate <code>~ClassC()</code> - although in reality finalizer methods are really rare and you shouldn't add them without good reason (unmanaged handles, etc)</p> <p>Re finalization order: no, there is no particular order followed, because full loops are possible - and it needs to be broken somewhere arbitrarily.</p>
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    1. USMarc Gravell
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    1. COMaybe I don't understand this, but does this answer the question? I see all answers describe finalizer behavior, but that seems kind of offtopic. Suppose `A` is "alive". It has only a weak reference to `B`. Clearly `B`-`C` are strongly connected. But can they be considered a "dead island", not referenced by "reachable" references? If `B`-`C` is dead, can we be sure `ClassB.DoSomething()` is not running? I guess this is what the Original Poster asked?
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      1. USJeppe Stig Nielsen
    2. CO@Jeppe Stig Nielsen I believe both Marc Gravell and dthorpe answered my question in the first few sentences of their posts. The extra information about finalizers was really just a bonus. The conclusion I took away from it is that it is always safe to access an object via a strong reference under all circumstances other than inside a finalizer. I trust that this includes the scenario that I addressed in my question where both the object holding the reference (B) and the referee (C) are on an island that is eligible for garbage collection.
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      1. USknick
    3. CO@knick OK, but Marc is saying _"then if the ClassB is still alive you don't need to worry [...]"_. But maybe the reason not to worry is that the `B` instance becoms alive again (from the dead?) when you pick up `.Target` on your weak reference? So how can the GC work? It can't know that someone might wake up `B` at any point in time. Will it collect `B` first, then `C`, because there's only a strong reference in one direction? (What if there were strong references in both directions, between `B` and `C`?)
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