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IWMBackupRestoreProps::GetPropByIndex 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 It has been superseded by Source Reader and Sink Writer.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.]

[GetPropByIndex is available for use in the operating systems specified in the Requirements section. It may be altered or unavailable in subsequent versions. Instead, use Microsoft PlayReady. ]

The GetPropByIndex method retrieves the name and value of a property by index.

This method is not implemented.

Syntax

HRESULT GetPropByIndex(
  [in]      WORD              wIndex,
  [out]     WCHAR             *pwszName,
  [in, out] WORD              *pcchNameLen,
  [out]     WMT_ATTR_DATATYPE *pType,
  [out]     BYTE              *pValue,
  [in, out] WORD              *pcbLength
);

Parameters

[in] wIndex

WORD containing the index of the property.

[out] pwszName

Pointer to a wide-character null-terminated string containing the name.

[in, out] pcchNameLen

On input, contains the length of pwszName. On output, points to a variable containing the number of characters in pwszName, including the terminating null character.

[out] pType

Pointer to a variable containing one member of the WMT_ATTR_DATATYPE enumeration type.

[out] pValue

Pointer to a byte array containing the value of the property.

[in, out] pcbLength

On input, contains the length of pValue. On output, points to a count of the bytes in pValue that are used.

Return value

The method returns E_NOTIMPL.

Remarks

You should make two calls to GetPropByIndex. On the first call, pass NULL for pwszName and pValue. On return, the value pointed to by pcchNameLen is set to the length in wide characters of the property name (including the terminating null character) and the value pointed to by pcbLength is set to the number of bytes required to hold the property value. You can then allocate buffers of the appropriate sizes to hold the values pwszName and pValue and pass pointers to them on the second call.

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

IWMBackupRestoreProps Interface

IWMBackupRestoreProps::SetProp