nf-combaseapi-cogettreatasclass.md

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NF:combaseapi.CoGetTreatAsClass	CoGetTreatAsClass function (combaseapi.h)	Returns the CLSID of an object that can emulate the specified object.	CoGetTreatAsClass CoGetTreatAsClass function [COM] _com_CoGetTreatAsClass com.cogettreatasclass combaseapi/CoGetTreatAsClass	com\cogettreatasclass.htm	com	f95fefe6-dc37-45f4-93be-87c996990ab9	12/05/2018	CoGetTreatAsClass, CoGetTreatAsClass function [COM], _com_CoGetTreatAsClass, com.cogettreatasclass, combaseapi/CoGetTreatAsClass	combaseapi.h	Objbase.h	Windows	Windows 2000 Professional [desktop apps only]	Windows 2000 Server [desktop apps only]										Ole32.lib	Ole32.dll		Windows			19H1	CoGetTreatAsClass combaseapi/CoGetTreatAsClass	c++	APIRef kbSyntax	DllExport	Ole32.dll API-MS-Win-Core-Com-l1-1-0.dll ComBase.dll API-MS-Win-Core-Com-l1-1-1.dll API-MS-Win-DownLevel-Ole32-l1-1-0.dll API-MS-Win-DownLevel-Ole32-l1-1-1.dll	CoGetTreatAsClass

CoGetTreatAsClass function

-description

Returns the CLSID of an object that can emulate the specified object.

-parameters

-param clsidOld [in]

The CLSID of the object that can be emulated (treated as) an object with a different CLSID.

-param pClsidNew [out]

A pointer to where the CLSID that can emulate clsidOld objects is retrieved. This parameter cannot be NULL. If there is no emulation information for clsidOld objects, the clsidOld parameter is supplied.

-returns

This function can return the following values, as well as any error values returned by the CLSIDFromString function.

Return code	Description
S_OK	A new CLSID was successfully returned.
S_FALSE	There is no emulation information for the clsidOld parameter, so the pClsidNew parameter is set to clsidOld.
REGDB_E_READREGDB	There was an error reading the registry.

-remarks

CoGetTreatAsClass returns the TreatAs entry in the registry for the specified object. The TreatAs entry, if set, is the CLSID of a registered object (an application) that can emulate the object in question. The TreatAs entry is set through a call to the CoTreatAsClass function. Emulation allows an application to open and edit an object of a different format, while retaining the original format of the object. Objects of the original CLSID are activated and treated as objects of the second CLSID. When the object is saved, this may result in loss of edits not supported by the original format. If there is no TreatAs entry for the specified object, this function returns the CLSID of the original object (clsidOld).

-see-also

CoTreatAsClass