Re: Destructors & Class Inheritance

From:
"Igor Tandetnik" <itandetnik@mvps.org>
Newsgroups:
microsoft.public.vc.language
Date:
Tue, 25 Apr 2006 17:18:52 -0400
Message-ID:
<eD8rb3KaGHA.504@TK2MSFTNGP03.phx.gbl>
dranger003@gmail.com wrote:

Let's say I have the following code:

// Start of Code

class ObjA {
 ~ObjA()
 {
   // Some Code
 }
};

class ObjB : public ObjA {
 int value;
 void DeleteMe()
 {
   delete this;
   value = 5;


This exhibits undefined behavior - you are accessing a member variable
of an object that has already been destroyed.

 }
};

ObjB *p = new ObjB;
ObjB->DeleteMe();

// End of Code

Deleting "this" in ObjB will also call the destructor in ObjA or not?


Yes it will.

What is the order of destruction, from ~ObjA to ~ObjB or the opposite?


~ObjB first, then ~ObjA.

Also, can I set value to 5 after the "delete this" in DeleteMe() ? I
would guess not... But I am not sure.


No you can't.
--
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    Igor Tandetnik

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