学步园

#include <iostream><br /> #include <atlbase.h><br /> using namespace std;</p> <p>interface IX : public IUnknown<br /> {<br /> virtual void _stdcall Fx() = 0;<br /> };</p> <p>interface IY : public IUnknown<br /> {<br /> virtual void _stdcall Fy() = 0;<br /> };</p> <p>interface IZ : public IUnknown<br /> {<br /> virtual void _stdcall Fz() = 0;<br /> };</p> <p>static const IID IID_IX = {0xec53e1de, 0x37d, 0x48f5, {0xa1, 0xee, 0x2d, 0xf5, 0xa5, 0xde, 0xf3, 0x49}}; // {EC53E1DE-037D-48f5-A1EE-2DF5A5DEF349}<br /> static const IID IID_IY = {0x4c510b77, 0xc63a, 0x4e0f, {0xa2, 0x45, 0x7b, 0x21, 0x23, 0x12, 0x23, 0xe7}};// {4C510B77-C63A-4e0f-A245-7B21231223E7}<br /> static const IID IID_IZ = {0xefb1f8d4, 0x674e, 0x4123, {0xa9, 0x19, 0x3c, 0x72, 0xee, 0xe8, 0x1d, 0x92}};// {EFB1F8D4-674E-4123-A919-3C72EEE81D92}</p> <p>class CA : public IX,<br /> public IY<br /> {<br /> public:<br /> CA() : m_cRef(0) { }<br /> virtual ~CA(){ }</p> <p>public:<br /> virtual HRESULT _stdcall QueryInterface(REFIID riid, __RPC__deref_out void **ppvObject);<br /> virtual ULONG _stdcall AddRef();<br /> virtual ULONG _stdcall Release();</p> <p> virtual void _stdcall Fx() { cout<<"CA::Fx"<<endl; }</p> <p> virtual void _stdcall Fy() { cout<<"CA::Fy"<<endl; }</p> <p>private:<br /> LONG m_cRef;<br /> };</p> <p>HRESULT _stdcall CA::QueryInterface(REFIID riid, __RPC__deref_out void **ppvObject)<br /> {<br /> if(IID_IX == riid)<br /> {<br /> *ppvObject = static_cast<IX*>(this);<br /> }<br /> else if(IID_IY == riid)<br /> {<br /> *ppvObject = static_cast<IY*>(this);<br /> }<br /> else if(IID_IUnknown == riid)<br /> {<br /> *ppvObject = static_cast<IX*>(this);<br /> }<br /> else<br /> {<br /> *ppvObject = NULL;<br /> return E_NOINTERFACE;<br /> }</p> <p> reinterpret_cast<IUnknown*>(*ppvObject)->AddRef(); //对应 这五个地方需要对应起来<br /> return S_OK;<br /> }</p> <p>ULONG _stdcall CA::AddRef()<br /> {<br /> InterlockedIncrement(&m_cRef);<br /> return m_cRef;<br /> }</p> <p>ULONG _stdcall CA::Release()<br /> {<br /> if(InterlockedDecrement(&m_cRef) == 0)<br /> {<br /> delete this; //下面标记的3个Release 缺少一个则执行不到这<br /> return 0;<br /> }</p> <p> return m_cRef;<br /> }</p> <p>IUnknown* CreateInstance()<br /> {<br /> IUnknown *pIUnk = static_cast<IX*>(new CA);<br /> pIUnk->AddRef(); //对应 这五个地方需要对应起来<br /> return pIUnk;<br /> }</p> <p>void _tmain(int argc,_TCHAR*argv[])<br /> {<br /> IUnknown *pIUnk = CreateInstance();</p> <p> IX *pIX = NULL;<br /> HRESULT hr = pIUnk->QueryInterface(IID_IX,(void**)&pIX);<br /> if(SUCCEEDED(hr))<br /> {<br /> pIX->Fx();<br /> pIX->Release(); //对应 这五个地方需要对应起来<br /> }</p> <p> IY *pIY = NULL;<br /> hr = pIUnk->QueryInterface(IID_IY,(void**)&pIY);<br /> if(SUCCEEDED(hr))<br /> {<br /> pIY->Fy();<br /> pIY->Release(); //对应 这五个地方需要对应起来<br /> }</p> <p> IZ *pIZ = NULL; //没有执行到AddRef，故不需要释放<br /> hr = pIUnk->QueryInterface(IID_IZ,(void**)&pIZ);<br /> if(SUCCEEDED(hr))<br /> {<br /> cout<<"found pIZ"<<endl;<br /> pIZ->Release();<br /> }</p> <p> pIUnk->Release(); //对应 这五个地方需要对应起来<br /> }