求助这段代码，看不明白

[shanyang1]

#pragma pack(pop)

//non-object API

typedef VOID (__stdcall *G33DDC_IF_CALLBACK)(CONST SHORT *Buffer,UINT32 NumberOfSamples,WORD MaxADCAmplitude,UINT32 ADCSamplingRate,DWORD_PTR UserData);
typedef VOID (__stdcall *G33DDC_DDC1_STREAM_CALLBACK)(CONST VOID *Buffer,UINT32 NumberOfSamples,UINT32 BitsPerSample,DWORD_PTR UserData);
typedef BOOL (__stdcall *G33DDC_DDC1_PLAYBACK_STREAM_CALLBACK)(VOID *Buffer,UINT32 NumberOfSamples,UINT32 BitsPerSample,DWORD_PTR UserData);
typedef VOID (__stdcall *G33DDC_DDC2_STREAM_CALLBACK)(UINT32 Channel,CONST FLOAT *Buffer,UINT32 NumberOfSamples,DWORD_PTR UserData);
typedef VOID (__stdcall *G33DDC_DDC2_PREPROCESSED_STREAM_CALLBACK)(UINT32 Channel,CONST FLOAT *Buffer,UINT32 NumberOfSamples,FLOAT SlevelPeak,FLOAT SlevelRMS,DWORD_PTR UserData);
typedef VOID (__stdcall *G33DDC_AUDIO_STREAM_CALLBACK)(UINT32 Channel,CONST FLOAT *Buffer,CONST FLOAT *BufferFiltered,UINT32 NumberOfSamples,DWORD_PTR UserData);
typedef BOOL (__stdcall *G33DDC_AUDIO_PLAYBACK_STREAM_CALLBACK)(UINT32 Channel,FLOAT *Buffer,UINT32 NumberOfSamples,DWORD_PTR UserData);

#pragma pack(push,1)

typedef struct
{
G33DDC_IF_CALLBACK IFCallback;
G33DDC_DDC1_STREAM_CALLBACK DDC1StreamCallback;
G33DDC_DDC1_PLAYBACK_STREAM_CALLBACK DDC1PlaybackStreamCallback;
G33DDC_DDC2_STREAM_CALLBACK DDC2StreamCallback;
G33DDC_DDC2_PREPROCESSED_STREAM_CALLBACK DDC2PreprocessedStreamCallback;
G33DDC_AUDIO_STREAM_CALLBACK AudioStreamCallback;
G33DDC_AUDIO_PLAYBACK_STREAM_CALLBACK AudioPlaybackStreamCallback;
} G33DDC_CALLBACKS;

#pragma pack(pop)

G33DDC_CALLBACKS里面哪些函数是可以直接调用的?调用方法，还有前面的typedef VOID (__stdcall....这种定义介绍一下

[gqjjqg]

函数指针，callbacks里如果 函数定义过并初始化到该结构体对象里，都可以调用吧....

[shanyang1]

另外还有：
BOOL G33DDCAPIWrapper::RegisterCallbacks(DDC2PreprocessedStreamCallback^ theDDC2PreprocessedStreamCallback, AudioStreamCallback^ theAudioStreamCallback)
{
if (ourModuleHandle == NULL)
{
Console::WriteLine("{0} not loaded", APILIBRARY);

return FALSE;
}

if (ourDeviceHandle < 0)
{
Console::WriteLine("Device not opened");

return FALSE;
}

ddc2PreprocessedStreamCallback = theDDC2PreprocessedStreamCallback; // Callback to C#
audioStreamCallback = theAudioStreamCallback; // Callback to C#

// DDC2PreprocessedStream-callback from unmanaged to managed C++
NotificationDDC2PreprocessedStreamCallbackDelegate^ aDDC2PreprocessedStreamDelegate = gcnew NotificationDDC2PreprocessedStreamCallbackDelegate(NotificationDDC2PreprocessedStreamCallback);
GCHandle aHandle = GCHandle::Alloc(aDDC2PreprocessedStreamDelegate);
IntPtr aPointer = Marshal::GetFunctionPointerForDelegate(aDDC2PreprocessedStreamDelegate);
G33DDC_DDC2_PREPROCESSED_STREAM_CALLBACK aDDC2PreprocessedStreamCallback = static_cast<G33DDC_DDC2_PREPROCESSED_STREAM_CALLBACK>(aPointer.ToPointer());

// AudioStreamCallback from unmanaged to managed C++
NotificationAudioStreamCallbackDelegate^ anAudioStreamCallbackDelegate = gcnew NotificationAudioStreamCallbackDelegate(NotificationAudioStreamCallback);
aHandle = GCHandle::Alloc(anAudioStreamCallbackDelegate);
aPointer = Marshal::GetFunctionPointerForDelegate(anAudioStreamCallbackDelegate);
G33DDC_AUDIO_STREAM_CALLBACK anAudioStreamCallback = static_cast<G33DDC_AUDIO_STREAM_CALLBACK>(aPointer.ToPointer());

// Force garbage collection cycle to prove that the delegate does not get disposed
GC::Collect();

// Registration of callbacks
ourCallbacks.IFCallback = NULL;
ourCallbacks.DDC1StreamCallback = NULL;
ourCallbacks.DDC1PlaybackStreamCallback = NULL;
ourCallbacks.DDC2StreamCallback = NULL;
ourCallbacks.DDC2StreamCallback = NULL;
ourCallbacks.DDC2PreprocessedStreamCallback = aDDC2PreprocessedStreamCallback;
ourCallbacks.AudioStreamCallback = anAudioStreamCallback;
ourCallbacks.AudioPlaybackStreamCallback = NULL;

// Register callbacks
ourSetCallbacks(ourDeviceHandle, &ourCallbacks, 0);

return TRUE;
}
红字那一段：RegisterCallbacks(DDC2PreprocessedStreamCallback^ theDDC2PreprocessedStreamCallback, AudioStreamCallback^ theAudioStreamCallback)
为啥参数是DDC2PreprocessedStreamCallback^ theDDC2PreprocessedStreamCallback, AudioStreamCallback^ theAudioStreamCallback，也就是func(a^a,b^b)的形式？？

[yiyefangzhou24]

额，这个代码写了一种动态调用库中函数的方法，首先用typedef申明函数类型，在实例华一个函数IFCallBack。他下面可能做的操作是LoadLibrary将库中的地址付给IFCallBack