com组件调用代码示例----续

 --Method 3--------------------------------------------------------
   CoInitialize(NULL);
   HRESULT hr;
   CLSID clsid;
   hr=CLSIDFromProgID(OLESTR("myCom.GetRes"),&clsid);
   IGetRes* ptr;
   IGetResEx* ptrEx;

   //使用CoCreateClassObject创建一个组件(特别是mutilThreads)的多个对象的
     时候，效率更高.
   IClassFactory* p_classfactory;
   hr=CoGetClassObject(clsid,CLSCTX_INPROC_SERVER,
                       NULL,IID_IClassFactory,
                       (LPVOID*)&p_classfactory);
   p_classfactory->CreateInstance(NULL,__uuidof(IGetRes),
                                          (LPVOID*)&ptr);
   p_classfactory->CreateInstance(NULL,__uuidof(IGetResEx),
                                          (LPVOID*)&ptrEx);
   ptr->Hello();
   ptrEx->HelloEx();
   CoUninitialize();