IWMIStreamProps::GetProperty method (wmsdkidl.h)

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The GetProperty method retrieves a named property from the IStream.

Syntax

HRESULT GetProperty(
  [in]      LPCWSTR           pszName,
  [out]     WMT_ATTR_DATATYPE *pType,
  [out]     BYTE              *pValue,
  [in, out] DWORD             *pdwSize
);

Parameters

[in] pszName

Pointer to a null-terminated string containing the name of the property to retrieve. You should use the global identifier to refer to properties so that any error will appear at compile time. The following table lists the available IStream properties.

[out] pType

Pointer to a variable that will receive one member of the WMT_ATTR_DATATYPE enumeration type. This value indicates the type of data in the buffer at pValue.

[out] pValue

Pointer to a byte buffer that will receive the property value. The type of data returned to the buffer is indicated by the value pointed to by pType.

[in, out] pdwSize

Pointer to a DWORD containing the size of the buffer at pValue. On return, this value will be set to the correct size of the property value.

Return value

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

Remarks

You should make two calls to GetProperty for each property you want to retrieve. On the first call, pass NULL as pValue. On return, the value pointed to by pdwSize will be set to the buffer size required to hold the property value. Then you can allocate the required amount of memory for the buffer and pass a pointer to it as pValue on the second call.

Requirements

See also

IWMIStreamProps Interface