HRESULT QueryInterface( REFIID iid, void** ppvObject );
Return Value
A standard HRESULT value.
Parameters
iid
[in] The identifier of the interface being requested.
ppvObject
[out] A pointer to the interface pointer identified by iid. If the object does not support this interface, ppvObject is set to NULL.
Remarks
Retrieves a pointer to the requested interface.
For an aggregated object, if the requested interface is IUnknown, QueryInterface returns a pointer to the aggregated object's own IUnknown and increments the reference count. Otherwise, this method queries for the interface through the CComContainedObject data member, m_contained.