COM and deriveing

[orafal]

Hello, is it possible to create a COM objects structure as below: In a dll library I define:

class T1
{
public:
STDMETHOD(Method)();
}

STDMETHODIMP T1::Method()
{
AFX_MANAGE_STATE(AfxGetStaticModuleState())

return S_OK;
}

which implements interface:

interface IT1 : IDispatch
{
[id(1)] HRESULT Method();
};

coclass T1
{
[default] interface IT1;
};

and then I would like to have:

class T2 : public T1
{
//something additional
}

I would like to create a COM objects from the class T2 and have all the functionality provided by class T1. E.g. I would like to call:

CComQIPtr spiT1(piT2);
spiT1->Method();

Anyone can help?

[kcynic]

have you had a try? if it didn't work, maybe you could define a new interface: interface IT2:IT1

[_Superman_]

Although this would work, T2 would be an ordinary class while T1 is a com class.

«_Superman_» I love work. It gives me something to do between weekends.

[CurtD]

I think you want to use aggregation. "To expose the interfaces of one COM class as though they were implemented on a second COM class, the second class aggregates the first. "