title	Compiler COM Support Classes | Microsoft Docs
ms.custom
ms.date	11/04/2016
ms.reviewer
ms.suite
ms.technology	cpp-language
ms.tgt_pltfrm
ms.topic	language-reference
f1_keywords	_com_raise_error
dev_langs	C++
helpviewer_keywords	cl.exe compiler, COM support COM, compiler support
ms.assetid	6d800d9b-b902-4033-9639-740a30b06f88
caps.latest.revision	6
author	mikeblome
ms.author	mblome
manager	ghogen

Compiler COM Support Classes

Microsoft Specific

Standard classes are used to support some of the COM types. The classes are defined in comdef.h and the header files generated from the type library.

Class	Purpose
_bstr_t	Wraps the BSTR type to provide useful operators and methods.
_com_error	Defines the error object thrown by _com_raise_error in most failures.
_com_ptr_t	Encapsulates COM interface pointers, and automates the required calls to AddRef, Release, and QueryInterface.
_variant_t	Wraps the VARIANT type to provide useful operators and methods.

END Microsoft Specific

See Also

Compiler COM Support
Compiler COM Global Functions
C++ Language Reference