IShellItemArray::GetPropertyStore method (shobjidl_core.h)
Gets a property store.
HRESULT GetPropertyStore( [in] GETPROPERTYSTOREFLAGS flags, [in] REFIID riid, [out] void **ppv );
One of the GETPROPERTYSTOREFLAGS constants.
The IID of the object type to retrieve.
If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.
This method is used to obtain a read-only property store that aggregates properties gathered from all the items in the shell item array.
If there is more than one item in the shell item array, then the resulting property store will aggregate the values from each item according to a set of rules determined by each property. Values read from the property store will be coerced to a canonical form prior to aggregation as discussed at CoerceToCanonicalValue. The output from a call to IPropertyStore::GetValue is computed as follows:
- Single valued properties follow the rule specified by the aggregation type string in the property description schema.
- If the aggregation type is "DateRange" and the property type is a filetime, returns a VT_VECTOR | VT_FILETIME of two values, or a VT_FILETIME value if the values were identical.
- If the aggregation type is "First", returns the first non-empty value.
- If the aggregation type is "Sum", returns the sum.
- If the aggregation type is "Average", returns the average of all non-empty values.
- If the aggregation type is "Minimum", returns the minimum value.
- If the aggregation type is "Union" and the property type is a string, returns a VT_VECTOR | VT_LPWSTR containing the union of values. The order of the values is unspecified.
- If the aggregation type is unspecified, incompatible, or "Default", either returns a single value if it is identical for all items in the array, or a special value used to indicate that the values differ between some of the items. The special value is a VT_VECTOR | VT_LPWSTR containing two strings: "Multiple" and "Values". Calling applications should check for this special value by checking for VT_VECTOR | VT_LPWSTR if GetTypeFlags indicates the property is single-valued.
- Multi-valued string properties return an intersection of their strings. The order is unspecified.
Calling applications may achieve other aggregation behaviors by accessing the individual shell items and their property stores directly. See IPropertyStore::GetCount, IPropertyStore::GetAt, and GetPropertyStore.
Writing to an array of shell items is supported via the IFileOperation API.
|Minimum supported client||Windows Vista [desktop apps only]|
|Minimum supported server||Windows Server 2008 [desktop apps only]|
|Header||shobjidl_core.h (include Shobjidl.h)|