Re: initializing a COM object with data not through an interface.

From:
"Igor Tandetnik" <itandetnik@mvps.org>
Newsgroups:
microsoft.public.vc.atl
Date:
Mon, 1 Jan 2007 10:59:42 -0500
Message-ID:
<ur92X3bLHHA.420@TK2MSFTNGP06.phx.gbl>
"kombat" <ohadpr@gmail.com> wrote in message
news:1167664509.576786.211140@a3g2000cwd.googlegroups.com

i have an ATL executable housing two objects, lets call them A and B.
one of A's methods creates a new instance of B and returns it, as in
returns a new COM object B.
i need A to initialize B with a few c++ classes.


The usual idiom goes like this:

STDMETHODIMP A::getB(IB** ppIB) {
    CComObject<B>* pB;
    CComObject<B>::CreateInstance(&pB);
    pB->AddRef();

    // At this point, you have a pointer to B (a class derived from B,
    // to be exact) and can call regular C++ methods on it,
    // not just those exposed via COM
    pB->Init(/* any C++ parameters */);

    HRESULT hr = pB->QueryInterface(IID_IB, (void**)ppIB);
    pB->Release();
    return hr;
}

--
With best wishes,
    Igor Tandetnik

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