/// <summary>
/// Retrieves a byte array associated with a key.
/// </summary>
/// <param name="attributes">A valid IMFAttributes instance.</param>
/// <param name="guidKey">Guid that identifies which value to retrieve.</param>
/// <param name="value">Receives the byte array.</param>
/// <returns>If this function succeeds, it returns the S_OK member. Otherwise, it returns another HResult's member that describe the error.</returns>
public static HResult GetAllocatedBlob(this IMFAttributes attributes, Guid guidKey, out byte[] value)
{
if (attributes == null)
{
throw new ArgumentNullException("attributes");
}
IntPtr resultPtr;
int resultLength;
HResult hr = attributes.GetAllocatedBlob(guidKey, out resultPtr, out resultLength);
if (hr.Succeeded())
{
try
{
value = new byte[resultLength];
Marshal.Copy(resultPtr, value, 0, resultLength);
}
finally
{
Marshal.FreeCoTaskMem(resultPtr);
}
}
else
{
value = null;
}
return(hr);
}
/// <summary>
/// Retrieves a <see cref="MemoryBuffer"/> associated with a key.
/// </summary>
/// <param name="attributes">A valid IMFAttributes instance.</param>
/// <param name="guidKey">Guid that identifies which value to retrieve.</param>
/// <param name="value">Receives a MemoryBuffer wrapping the attribute content.</param>
/// <returns>If this function succeeds, it returns the S_OK member. Otherwise, it returns another HResult's member that describe the error.</returns>
public static HResult GetAllocatedBlob(this IMFAttributes attributes, Guid guidKey, out MemoryBuffer value)
{
if (attributes == null)
{
throw new ArgumentNullException("attributes");
}
IntPtr resultPtr;
int resultLength;
HResult hr = attributes.GetAllocatedBlob(guidKey, out resultPtr, out resultLength);
value = hr.Succeeded() ? new MemoryBuffer(resultPtr, (uint)resultLength) : null;
return(hr);
}
public HResult GetAllocatedBlob(Guid guidKey,
out IntPtr ip, out int pcbSize)
{
return(m_Attribs.GetAllocatedBlob(guidKey, out ip, out pcbSize));
}