iunknown-implementation-classes.md

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IUnknown Implementation Classes (ATL) | Microsoft Docs		11/04/2016			cpp-windows		article	vc.atl.Iunknown	C++	IUnknown implementation classes	47b69bb5-69d8-4a9c-84a8-329bdde2bb3f	10	mikeblome	mblome	ghogen

IUnknown Implementation Classes

The following classes implement IUnknown and related methods:

• CComObjectRootEx Manages reference counting for both aggregated and nonaggregated objects. Allows you to specify a threading model.

• CComObjectRoot Manages reference counting for both aggregated and nonaggregated objects. Uses the default threading model of the server.

• CComAggObject Implements IUnknown for an aggregated object.

• CComObject Implements IUnknown for a nonaggregated object.

• CComPolyObject Implements IUnknown for aggregated and nonaggregated objects. Using CComPolyObject avoids having both CComAggObject and CComObject in your module. A single CComPolyObject object handles both aggregated and nonaggregated cases.

• CComObjectNoLock Implements IUnknown for a nonaggregated object, without modifying the module lock count.

• CComTearOffObject Implements IUnknown for a tear-off interface.

• CComCachedTearOffObject Implements IUnknown for a "cached" tear-off interface.

• CComContainedObject Implements IUnknown for the inner object of an aggregation or a tear-off interface.

• CComObjectGlobal Manages a reference count on the module to ensure your object won't be deleted.

• CComObjectStack Creates a temporary COM object, using a skeletal implementation of IUnknown.

Related Articles

Fundamentals of ATL COM Objects

See Also

Class Overview
Aggregation and Class Factory Macros
COM Map Macros
COM Map Global Functions