一.使用IDispatch

interface IRandom : IDispatch{    import "oaidl.idl";    [id(0)]    HRESULT Start([out]long* pnID);    [id(1)]    HRESULT Stop([in]long nID);    [id(2)]    HRESULT StopAll();};

使用GetIDsOfNames获取DISP

OLECHAR *fn=L"Stop";DISPID id;pRandom->GetIDsOfNames(IID_NULL,&fn,1,GetUserDefaultLCID(),&id);

使用Invoke动态调用函数

VARIANT var;::VariantInit(&var);var.lVal=2;DISPPARAMS params;params.cArgs=1;params.rgvarg=&var;pRandom->Invoke(id,IID_NULL,GetUserDefaultLCID(),DISPATCH_METHOD,    &params,NULL,NULL,NULL);

跟反射的概念完全是一样的

二.IDispatchImpl

ATL中,IDispatchImpl实现了IDispatch

class CRandom :    public IDispatchImpl
    
     ,{public:    CRandom()    {    }    ~CRandom();BEGIN_COM_MAP(CRandom)    COM_INTERFACE_ENTRY2(IDispatch, IRandom)    COM_INTERFACE_ENTRY(IRandom)END_COM_MAP() }
    

三.实现连接点

1.实现IConnectionPointContainerImpl和IConnectionPointImpl

class CRandom :    public IConnectionPointContainerImpl
    
     ,    public IConnectionPointImpl
    

2.在客户端调用方实现IRandomEvent接口(接收器)

class CDriver :    public IDispatchImpl
    
     ,    public CComObjectRoot{public:    CDriver() {}BEGIN_COM_MAP(CDriver)    COM_INTERFACE_ENTRY(IDispatch)    COM_INTERFACE_ENTRY(IRandomEvent)END_COM_MAP()// IRandomEvent    STDMETHOD(Fire)(long l);public:};
    

3.客户端创建连接点进行监听

CComObject
    
     * pDriver;CComObject
     
      ::CreateInstance(&pDriver);pDriver->m_nID = m_nAdviseCnt;HRESULT hRes = AtlAdvise(pRandom, pDriver->GetUnknown(), IID_IRandomEvent, &m_arrAdvise[m_nAdviseCnt++]);
     
    

4.服务器端进行回调

IConnectionPointImpl
    
     * p = this;Lock();HRESULT hr = S_OK;IUnknown** pp = p->m_vec.begin();while (pp < p->m_vec.end() && hr == S_OK){    if (*pp != NULL)    {        IRandomEvent* pIRandomEvent = (IRandomEvent*)*pp;        hr = pIRandomEvent->Fire(nID);    }    pp++;}
    

5.自动生成连接点代理

第4步可以用vs自动生成代码,如果事件很多(而且客户端可以多次监听),写这些重复的代码是没有必要的

template
    
     class CProxyIRandomEvent :    public ATL::IConnectionPointImpl
     
      {public:    HRESULT Fire_Fire(long nID)    {        HRESULT hr = S_OK;        T * pThis = static_cast
      
       (this);        int cConnections = m_vec.GetSize();        for (int iConnection = 0; iConnection < cConnections; iConnection++)        {            pThis->Lock();            CComPtr
       
         punkConnection = m_vec.GetAt(iConnection);            pThis->Unlock();            IRandomEvent * pConnection = static_cast
        
         (punkConnection.p);            if (pConnection)            {                hr = pConnection->Fire(nID);            }        }        return hr;    }};
        
       
      
     
    

 

class CRandom :    public IDispatchImpl
    
     ,    public IConnectionPointContainerImpl
     
      ,    public CProxyIRandomEvent
      
       {public:    CRandom()    {    }    ~CRandom();// Connection Point1    BEGIN_CONNECTION_POINT_MAP(CRandom)        CONNECTION_POINT_ENTRY(__uuidof(IRandomEvent))    END_CONNECTION_POINT_MAP()
      
     
    

让CRandom 继承自CProxyIRandomEvent,去掉之前的IConnectionPointImpl