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IWMReaderAdvanced::GetStreamSelected method (wmsdkidl.h)

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 It has been superseded by Source Reader and Sink Writer.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

The GetStreamSelected method ascertains whether a particular stream is currently selected. This method can be used only when manual stream selection has been specified.

Syntax

HRESULT GetStreamSelected(
  [in]  WORD                 wStreamNum,
  [out] WMT_STREAM_SELECTION *pSelection
);

Parameters

[in] wStreamNum

WORD containing the stream number. Stream numbers are in the range of 1 through 63.

[out] pSelection

Pointer to one member of the WMT_STREAM_SELECTION enumeration type.

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.
E_INVALIDARG
The pSelection parameter is NULL, or the stream number is invalid.
E_UNEXPECTED
The method failed for an unspecified reason.
NS_E_INVALID_REQUEST
The reader object has not opened a file yet.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only],Windows Media Format 7 SDK, or later versions of the SDK
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header wmsdkidl.h (include Wmsdk.h)
Library Wmvcore.lib; WMStubDRM.lib (if you use DRM)

See also

IWMReaderAdvanced Interface

IWMReaderAdvanced::SetStreamsSelected

To Use Manual Stream Selection

WMT_STREAM_SELECTION