CSharp/C#, garbage collect--is a bug?

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CSharp/C# >> garbage collect--is a bug?

by Michael C » Sun, 31 Aug 2008 09:25:24 GMT

"chinasprit" < XXXX@XXXXX.COM > wrote in message
news: XXXX@XXXXX.COM ...
> static tc gto;
>
> public class tc
> {
> public int a=99;
>
> ~tc()
> {
> a=-1; //set breakpoint 1
> gto=this;
> }
> }
>
> private void button1_Click(object sender,EventArgs e)
> {
> tc to=new tc();
> GC.Collect();
> GC.WaitForPendingFinalizers();
> return; // set breakpoint 2
> }
>
> two problems:
> click button once,it seem the ~tc() not execute at all.and it will excute
> at
> the second time clicking.why?

I remember reading something about the GC disposing objects on the first run
(if they have IDispose) and destroying them on the second run. If that is
the case then your second point makes sense because you're looking at 2
different objects and the second object has not been disposed yet.

> the second clicking,breakpoint 2, "gto" and "to", gto.a=-1,while
> to.a=99,why?



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CSharp/C# >> garbage collect--is a bug?

by Jon Skeet [C# MVP] » Sun, 31 Aug 2008 14:19:35 GMT



The garbage collector itself doesn't know about IDisposable at all. It
calls finalizers, which may in turn call Dispose, but it doesn't call
Dispose directly itself.

--
Jon Skeet - < XXXX@XXXXX.COM >
Web site: http://www.pobox.com/ ~skeet
Blog: http://www.msmvps.com/jon.skeet
C# in Depth: http://csharpindepth.com
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CSharp/C# >> garbage collect--is a bug?

by Gan Andersson » Sun, 31 Aug 2008 17:16:23 GMT


Not exactly.

If an object that is unreachable has a finalizer, it will be placed on
the freachable queue, where a background thread will execute the
finalizer. After the finalizer has been run, the object can be collected
just like any other object.



--
G鰎an Andersson
_____
http://www.guffa.com
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