CWnd::GetControlUnknown
LPUNKNOWN GetControlUnknown( );
Return Value
A pointer to the interface of the OLE control represented by this CWnd object. If this object does not represent an OLE control, the return value is NULL.
Remarks
Call this member function to retrieve a pointer to an unknown OLE control. You should not release this IUnknown pointer. Typically, you would use to obtain a specific interface of the control.
The interface pointer returned by GetControlUnknown is not reference-counted. Do not call on the pointer unless you have previously called on it.