com-error-com-error.md

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Learn more about: _com_error::_com_error	_com_error::_com_error	11/17/2022	COMDEF/_com_error _com_error::_com_error	_com_error constructor [C++]	0a69e46c-caab-49ef-b091-eee401253ce6

_com_error::_com_error

Microsoft Specific

Constructs a _com_error object.

Syntax

_com_error(
   HRESULT hr,
   IErrorInfo* perrinfo = NULL,
   bool fAddRef = false) throw();

_com_error( const _com_error& that ) throw();

Parameters

hr
HRESULT information.

perrinfo
IErrorInfo object.

fAddRef
The default causes the constructor to not call AddRef on a non-null IErrorInfo interface. This behavior provides for correct reference counting in the common case where ownership of the interface is passed into the _com_error object, such as:

throw _com_error(hr, perrinfo);

If you don't want your code to transfer ownership to the _com_error object, and the AddRef is required to offset the Release in the _com_error destructor, construct the object as follows:

_com_error err(hr, perrinfo, true);

that
An existing _com_error object.

Remarks

The first constructor creates a new object given an HRESULT and optional IErrorInfo object. The second creates a copy of an existing _com_error object.

END Microsoft Specific

See also

_com_error class