c# - c++ native 代码 DLL 使用抽象类到包装器中以在 C# 模块中使用

Question

您好，我在抽象类方面遇到了同样的问题。我正在尝试包装我的 cpp Dll 调用以在 C# 模块中使用。

Dll 正在使用工厂模式。其中包含一个类 Factory、MiddileWare 和它们的共同strong textresponding 子类。任何人都可以帮助我启动包装器。我被困在这之间。您的帮助将不胜感激。我在这里给出流程:

中间件工厂.h

#pragma once
#include "MiddleWareConnection.h"
#include "std afx.h"

  #ifdef MIDDLEWAREFACTORY_EXPORTS
#define MIDDLEWAREFACTORY_API __declspec(dllexport)
#else

#define MIDDLEWAREFACTORY_API __declspec(dllimport) #endif

  MIDDLEWAREFACTORY_API enum eMiddleWareEngine
      {
          eRabitMQ = 0,  
          eZeroMQ,                           
          eActiveMQ          

        };
     // This class is exported from the MiddleWareFactory.dll

      class MIDDLEWAREFACTORY_API CMiddleWareFactory
      {
      public:
         CMiddleWareFactory(void);
         ~CMiddleWareFactory();
        // TODO: add your methods here.

        //Function to Create the  object of Broker module:implemnted the                   Factory   concept.
      BOOL CreateInstance(CMiddleWareConnection** pMObj);
     int m_eMomEngine;//To define which MOM need to enable.

};



extern MIDDLEWAREFACTORY_API int nMiddleWareFactory;

MIDDLEWAREFACTORY_API int fnMiddleWareFactory(void);

中间件连接.h

#pragma一次

类 CMiddleWareConnection { 公共(public):

  virtual ~CMiddleWareConnection(void)
  {
   }
  //Pure virtual fuctions for interfacing 
  virtual BOOL Connect(int nServerType)=0;
   virtual BOOL CreateSessionExchange() = 0;
   virtual BOOL CreateQueue(LPCTSTR lpszQueueName) = 0;
   virtual BOOL Disconnect() = 0;
   virtual BOOL Send(void *MomItem,LPCTSTR lpszKey, int               &nSendCount)=0;
   virtual BOOL Receive() = 0;
   virtual void StopReceiver() = 0;
   virtual void GetData(void* pMsg, int &nMsgLen,int nMsgType,int &nReceiveCount)=0;
   };

RabbitMQ.h

  #pragma once
  #include "MiddleWareConnection.h"
  #include "Amqp.h"
  #pragma comment(lib, "rabbitmq.4.lib")
  #define GET_DATA(a){memcpy(&a, pDataPtr,  sizeof(a));pDataPtr+=sizeof(a);}
  #define GET_DATA_EX(s,n){memcpy(s, pDataPtr, n);pDataPtr+=n;}

 typedef struct _ROUTINE_KEY
{
 CString RoutingKey;             

 }ROUTEKEY, *LPROUTEKEY;

   class CRabbitMQ :
   public CMiddleWareConnection
      {
          public:

      CRabbitMQ(CAppConfig &rConfig);
     ~CRabbitMQ();
      void   InitializeRBMQ(CAppConfig &rConfig);//Initialize RBMQ Config;
         BOOL   Connect(int nServerType);
         BOOL   Disconnect(void);
         BOOL   Send(void *MomItem, LPCTSTR lpszKey, int &nSendCount);
         BOOL   Receive(void);
         BOOL   CreateQueue(LPCTSTR lpszQueueName);
         BOOL   CreateSessionExchange();
         BOOL   BindQueue(LPCTSTR lpszQueue, LPCTSTR lpszExchangeName, LPCTSTR lpszKey);
         bool   IsConnected(){return m_bConnected;}
         void   SetKeyQueueCombination( TCHAR *pszQueueName, TCHAR *pszRoutingKey);
         void   StopReceiver();
         bool   ReEstablishRMQMWConnection();
        void   GetData(LPBYTE &pMsg, int &nMsgLen,int &nReceiveCount);
        void   GetData(void* pMsg, int &nMsgLen,int nMsgType,int &nReceiveCount);
     BOOL   GetNext_JasonListItem(LPJASON_ITEM pItem);
      LPRABBIT_MQ_ITEM GetNextItem();

      };

在这里，我想公开 rabbitMq 类函数[从 MiddleWareConnection.h 到 C# 模块的连接、发送、接收等。

谢谢

Answer 1

下面我发布了一个包装 C++/CLI 类的小代码示例。您可以创建一个新的 C++/CLI 项目，它链接您的 native 库并按照下面的示例创建一个类。这将生成一个托管程序集，您可以从 C# 端引用它。希望对您有所帮助!

#include <Windows.h>
#include <vcclr.h>  

using namespace System;
using namespace System::Text;
using namespace System::Collections::Generic;
using namespace System::Runtime::InteropServices;

public ref class CMiddleWareConnection_Net
{
  public:

    CMiddleWareConnection_Net()
    {
        pMiddleWareConnection = NULL;
    }

    ~CMiddleWareConnection_Net()
    {
        //Release pMiddleWareConnection
        if (pMiddleWareConnection)
            delete pMiddleWareConnection;
    }

    void   InitializeRBMQ(CAppConfig_Net config)
    {
        // CAppConfig_Net is another ref class 
        // which provides a toNative method 
        // returning a plain C++ CAppConfig object
        CAppConfig rConfig = config.toNative();  

        pMiddleWareConnection = CRabbitMQ(rConfig);
    }

    bool   Connect(int nServerType)
    {
        return (pMiddleWareConnection->Connect(nServerType) == TRUE);
    }

    bool   Disconnect(void)
    {
        return (pMiddleWareConnection->Disconnect() == TRUE);
    }

    bool   Send(array<Byte>^ MomItem, String^ lpszKey, int% nSendCount)
    {
        //Assuming MomItem is a byte array...
        unsigned char *pData = new unsigned char[MomItem->Length];
        Marshal::Copy(MomItem, 0, IntPtr(pData), MomItem->Length);          

        //Marshal String^ to LPCSTR
        IntPtr ip = Marshal::StringToHGlobalAnsi(lpszKey);  
        LPCSTR str = static_cast<LPCSTR>(ip.ToPointer());

        bool bRet = (pMiddleWareConnection->Send(pData, str, nSendCount) == TRUE);

        //Freeing memory
        delete[] pData;
        Marshal::FreeHGlobal(ip);

        return bRet;
    }

    bool   Receive(void)
    {
        return (pMiddleWareConnection->Receive() == TRUE);
    }

    /* Other methods */
    ... 

  private:
    CMiddleWareConnection *pMiddleWareConnection;

};