Re: Self deleting class
"Lisa Pearlson" <no@spam.plz> wrote in message
news:u6xHp9mFIHA.1204@TK2MSFTNGP03.phx.gbl...
Hi,
Imagine:
CSomeClass* c = NULL;
c = new CSomeClass();
delete c;
c = new CSomeClass();
delete c;
So I must call delete c; to clean up memory.
However, instead of doing it like so.. isn't it equally valid to make
class self deleting?
So, if I do this:
class CSomeClass
{
CSomeClass();
virtual ~CSomeClass() { delete this; }
No! Not in the destructor.
This is ok though:
virtual void Release() { delete this; }
It is often combined with reference counting, a single threaded version
might look like:
int m_useCount;
virtual void AddRef() { m_useCount++; }
virtual void Release() { if (0 == --m_useCount) delete this; }
The other advantage of a self-deleting class is that it uses the memory
manager where the class is defined. When using DLLs you should respect
memory ownership and the same library that defines an object must both
create and destroy it, usually by using a factory function and a
self-deleting member function.
}
can I then simply do this?
CSomeClass* c = NULL;
c = new CSomeClass();
c = new CSomeClass();
What happens when I reassign the valiable to new instance? Will CSomeClass
self-delete itself at that point, or when application terminates?
Lisa
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