Question

我有一些C ++代码：

namespace Compute {   
  class __declspec(dllexport) IProgressCB {   
  public:     
    virtual void progress(int percentCompleted) = 0;   
  };    
  double __declspec(dllexport) compute(IProgressCB *progressCB, ...); 
}

我需要从C＃打电话。
因此，我想在C ++ / CLI中包装此C ++代码。

我理解如何包装compute（）函数，但是如何包装IProgress接口呢？

（似乎.Net类不可能继承C ++类？）

Answer 1

使用ref class，其中包含指向包装实例的指针：

namespace ComputeCLI {
    public ref class IProgressCB{
    public:
        void progress(int percentCompleted)
        {
            // call corresponding function of the wrapped object
            m_wrappedObject->progress(percentCompleted);
        }

    internal:
       // Create the wrapper and assign the wrapped object
       IProgressCB(Compute::IProgressCB* wrappedObject) 
            : m_wrappedObject(wrappedObject){}

        // The wrapped object
        Compute::IProgressCB* m_wrappedObject;
    };

    public ref class StaticFunctions{
    public:
        static double compute(IProgressCB^ progressCB, ...){
            Compute::compute(progressCB->m_wrappedObject, ...);
        }
    };
}

Answer 2

这个框架应该让你开始：

interface class IProgressEventSink
{ ... };

class ProgressEventForwarder : IProgressEventCB
{
    gcroot<IProgressEventSink^> m_sink;
public:
    ProgressEventForwarder(IProgressEventSink^ sink) : m_sink(sink) {}

// IProgressEventCB implementation
    virtual void OnProgress( ProgressInfo info ) { m_sink->OnProgress(info.a, info.b); }
};

ref class ComputeCLI
{
     Compute* m_pimpl;
 // ...

public:
     RegisterHandler( IProgressEventSink^ sink )
     {
         // assumes Compute deletes the handler when done
         // if not, keep this pointer and delete later to avoid memory leak
         m_pimpl->RegisterHandler(new ProgressEventForwarder(sink));
     }
};

如何在C ++ / CLI中包装C ++接口（抽象类）？

2 个答案: