Share via

_com_error Class

  • Article

Microsoft Specific

A _com_error object represents an exception condition detected by the error-handling wrapper functions in the header files generated from the type library or by one of the COM support classes. The _com_error class encapsulates the HRESULT error code and any associated IErrorInfo Interface object.

Construction

_com_error

Constructs a _com_error object.

Operators

operator =

Assigns an existing _com_error object to another.

Extractor Functions

Error

Retrieves the HRESULT passed to the constructor.

ErrorInfo

Retrieves the IErrorInfo object passed to the constructor.

WCode

Retrieves the 16-bit error code mapped into the encapsulated HRESULT.

IErrorInfo Functions

Description

Calls IErrorInfo::GetDescription function.

HelpContext

Calls IErrorInfo::GetHelpContext function.

HelpFile

Calls IErrorInfo::GetHelpFile function

Source

Calls IErrorInfo::GetSource function.

GUID

Calls IErrorInfo::GetGUID function.

Format Message Extractor

ErrorMessage

Retrieves the string message for HRESULT stored in the _com_error object.

ExepInfo.wCode to HRESULT Mappers

HRESULTToWCode

Maps 32-bit HRESULT to 16-bit wCode.

WCodeToHRESULT

Maps 16-bit wCode to 32-bit HRESULT.

Requirements

Header: comdef.h

Lib: comsuppw.lib or comsuppwd.lib (see /Zc:wchar_t (wchar_t Is Native Type) for more information)

See Also

Reference

Compiler COM Support Classes

IErrorInfo Interface

Change History

Date

History

Reason

December 2008

Linked to the "IErrorInfo Interface" topic. Updated formatting.

Customer feedback.