Problem making a C++ DLL in Visual Studio 2010 work in LabView

Question

Hello, I've noticed that I cannot do ' extern "C" ' on the methods Open(), Close(), StartStreaming(), and StopStreaming() in the following Class:
class ApplicationIo : public FiclIo
    friend class X5ScriptPlayer;
    friend class ApplicationSettings;
    typedef std::vector<__int64>    IntArray;
public:
    //  Member Functions
    ApplicationIo(IUserInterface * ui);
    ~ApplicationIo();
    ModuleIo &  ModIo()
        {  return Module;  }
    unsigned int BoardCount();
    void Open();
    bool IsOpen()
        {  return Opened;  }
    void Close();
    void StartStreaming();
    void StopStreaming();
How can I export the methods of the Class mentioned above? I've read the manuals and seen examples about how to get DLLs working in LabView, however none of them ever talk about when there is an actual Class involved and exporting the methods of said Class.
Any help would be greatly appreciated.

Answer 1

Okay, well at least that clears up one piece of the puzzle.
Here is the wrapper I need:
Here's the .h of the wrapper:
#ifndef _APPIO_DLL_WRAPPER_H_
#define _APPIO_DLL_WRAPPER_H_
#define DLLEXPORT __declspec (dllexport)
#ifdef __cplusplus
extern "C" {
#endif
typedef struct ApplicationIo ApplicationIo; /* make the class opaque to the wrapper */
DLLEXPORT ApplicationIo* Construct_AppIo(IUserInterface* ui);
DLLEXPORT void Destruct_AppIo(ApplicationIo* LV_Ref);
DLLEXPORT void Open(ApplicationIo* LV_Ref);
DLLEXPORT void Close(ApplicationIo* LV_Ref);
DLLEXPORT void StartStreaming(ApplicationIo* LV_Ref);
DLLEXPORT void StopStreaming(ApplicationIo* LV_Ref);
#ifdef __cplusplus
#endif
#endif /* _APPIO_DLL_WRAPPER_H_ */
Here's the .cpp of the wrapper:
#include "AppIoDll.h"
#include "ApplicationIo.h"
ApplicationIo* Construct_AppIo(IUserInterface* ui)
return new ApplicationIo(ui);
void Destruct_AppIo(ApplicationIo* LV_Ref)
LV_Ref->Close();
delete LV_Ref;
void Open(ApplicationIo* LV_Ref)
LV_Ref->Open();
void Close(ApplicationIo* LV_Ref)
LV_Ref->Close();
void StartStreaming(ApplicationIo* LV_Ref)
LV_Ref->StartStreaming();
void StopStreaming(ApplicationIo* LV_Ref)
LV_Ref->StopStreaming();
The one problem I have with this is how am I supposed to get the pointer to the IUserInterface class to the C Wrapper constructor?