IWMPropertyVault::GetPropertyByIndex method (wmsdkidl.h)

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The GetPropertyByIndex method retrieves a property from the vault by its index value.

Syntax

HRESULT GetPropertyByIndex(
  [in]      DWORD             dwIndex,
  [out]     LPWSTR            pszName,
  [in, out] DWORD             *pdwNameLen,
  [out]     WMT_ATTR_DATATYPE *pType,
  [out]     BYTE              *pValue,
  [in, out] DWORD             *pdwSize
);

Parameters

[in] dwIndex

DWORD containing the property index.

[out] pszName

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

[in, out] pdwNameLen

On input, a pointer to a DWORD containing the length, in wide characters, of the string at pszName. On output, specifies the number of characters, including the terminating null character, required to hold the property name.

[out] pType

Pointer to a member of the WMT_ATTR_DATATYPE enumeration type. This parameter specifies the type of data pointed to by pValue.

[out] pValue

Pointer to a data buffer containing the value of the property. This value can be one of several types. The type of data that the buffer contains on output is specified by the value of pType.

[in, out] pdwSize

Pointer to a DWORD containing the size, in bytes, of the data at pValue.

Return value

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

Remarks

You must make two calls to GetPropertyByIndex to properly retrieve all of the information. On the first call, pass NULL for both pszName and pValue. When the call returns, pdwNameLen and pdwSize point to the correct sizes of their respective buffers. Then on the second call, pass properly sized buffers as pszName and pValue to receive the data.

Requirements

See also

IWMPropertyVault Interface

IWMPropertyVault::GetPropertyByName

IWMPropertyVault::SetProperty