PropVariantToCLSID function (propvarutil.h)
Extracts class identifier (CLSID) property value of a PROPVARIANT structure.
Syntax
HRESULT PropVariantToCLSID(
[in] REFPROPVARIANT propvar,
[out] CLSID *pclsid
);
Parameters
[in] propvar
Type: REFPROPVARIANT
Reference to a source PROPVARIANT structure.
[out] pclsid
Type: CLSID*
When this function returns, contains the extracted property value if one exists.
Return value
Type: HRESULT
If this function succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.
Remarks
This helper function works forPROPVARIANT structures of the following types:
- VT_CLSID
- VT_BSTR
- VT_LPWSTR
- VT_ARRAY | VT_UI1
PropVariantToCLSID is used in places where the calling application expects a PROPVARIANT to hold a single CLSID or GUID value. For instance, an application obtaining values from a property store can use this to safely extract the CLSID value for GUID properties.
Examples
The following example, to be included as part of a larger program, demonstrates how to use PropVariantToCLSID to access a CLSID value in a PROPVARIANT.
// IPropertyStore *ppropstore;
// Assume variable ppropstore is initialized and valid
PROPVARIANT propvar = {0};
HRESULT hr = ppropstore->GetValue(PKEY_Sync_HandlerCollectionID, &propvar);
if (SUCCEEDED(hr))
{
// PKEY_Sync_HandlerCollectionID is expected to produce a VT_CLSID or VT_EMPTY value.
// PropVariantToCLSID will convert VT_EMPTY to a failure code.
CLSID clsidCollectionID;
hr = PropVariantToCLSID(propvar, &clsidCollectionID);
if (SUCCEEDED(hr))
{
// clsidCollectionID is now valid
}
else
{
// the extraction failed
}
PropVariantClear(&propvar);
}
Requirements
Requirement | Value |
---|---|
Minimum supported client | Windows XP with SP2, Windows Vista [desktop apps only] |
Minimum supported server | Windows Server 2003 with SP1 [desktop apps only] |
Target Platform | Windows |
Header | propvarutil.h |
Redistributable | Windows Desktop Search (WDS) 3.0 |