C#调用C++写的下载网络流的sourcefilter解决方案

DECLARE_INTERFACE_(INetReceiver, IUnknown)
{
    STDMETHOD(SetStreamType) (THIS_
        long inType
    ) PURE;

    STDMETHOD(SetSize) (THIS_
        long inTotalSize, long inCheckOffset
    ) PURE;

    STDMETHOD(SetStreamSocket) (THIS_
        SOCKET inSocket    
    ) PURE;

    STDMETHOD(StartReceiving) (THIS) PURE;

    STDMETHOD(StopReceiving) (THIS) PURE;

    STDMETHOD(CanConnectToDownstream) (THIS) PURE;
};

[ComImport, Guid("3F565AA9-3004-4f82-8882-174D51C73332")]
    public class FilterNetReceiver
    {
    }
    [Guid("8D2AE29A-2783-416c-B40F-790E2FE83267"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    public interface ISourceFilter
    {
        [PreserveSig]
        bool SetStreamType(long inType);
        [PreserveSig]
        bool SetSize(long inTotalSize, long inCheckOffset);
        [PreserveSig]
        bool SetStreamSocket(Socket inSocket);
        [PreserveSig]
        bool StartReceiving();
        [PreserveSig]
        bool StopReceiving();
        [PreserveSig]
        bool CanConnectToDownstream();

    }