IWMPMediaCollection2::getStringCollectionByQuery method (wmp.h)

Artículo
4/26/2023

[The feature associated with this page, Windows Media Player SDK, is a legacy feature. It has been superseded by MediaPlayer. MediaPlayer has been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer instead of Windows Media Player SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The getStringCollectionByQuery method retrieves a pointer to an IWMPStringCollection interface. This interface represents a set of all string values for a specified attribute that match the query conditions.

Syntax

HRESULT getStringCollectionByQuery(
  [in]  BSTR                 bstrAttribute,
  [in]  IWMPQuery            *pQuery,
  [in]  BSTR                 bstrMediaType,
  [in]  BSTR                 bstrSortAttribute,
  [in]  VARIANT_BOOL         fSortAscending,
  [out] IWMPStringCollection **ppStringCollection
);

Parameters

[in] bstrAttribute

String containing the attribute name.

[in] pQuery

Pointer to the IWMPQuery interface that represents the query that defines the conditions used to retrieve the string collection.

[in] bstrMediaType

String containing the media type. Must contain one of the following values: "audio", "video", "photo", "playlist", or "other".

[in] bstrSortAttribute

String containing the attribute name used for sorting. An empty string means no sorting is applied.

[in] fSortAscending

VARIANT_BOOL that indicates whether the playlist must be sorted in ascending order.

[out] ppStringCollection

Address of a variable that receives a pointer to an IWMPStringCollection interface for the retrieved set of string values.

Return value

The method returns an HRESULT. Possible values include, but are not limited to, those in the following table.

Return code	Description
S_OK	The method succeeded.

Remarks

Compound queries using IWMPQuery are not case sensitive.

When the compound query specified by the pQuery parameter contains a condition built on the MediaType attribute, that condition is ignored. The value for the bstrMediaType parameter is always used. For example, if the compound query contains the condition "MediaType Equals audio" and the value for the bstrMediaType parameter is "video", the resulting playlist will contain only video items.

Windows Media Player 10 Mobile: This method is not supported.

Requirements

Requirement	Value
Minimum supported client	Windows Media Player 11.
Target Platform	Windows
Header	wmp.h
DLL	Wmp.dll

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