IWMBackupRestoreProps::GetPropByIndex method (wmsdkidl.h)

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[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

See also

IWMBackupRestoreProps Interface

IWMBackupRestoreProps::SetProp