the CComObjectRootEx

 

template <class ThreadModel>
class CComObjectRootEx : public CComObjectRootBase
{
public:
 typedef ThreadModel _ThreadModel;
 typedef typename _ThreadModel::AutoCriticalSection _CritSec;
 typedef typename _ThreadModel::AutoDeleteCriticalSection _AutoDelCritSec;
 typedef CComObjectLockT<_ThreadModel> ObjectLock;

 ~CComObjectRootEx() {}

 ULONG InternalAddRef()
 {
  ATLASSUME(m_dwRef != -1L);
  return _ThreadModel::Increment(&m_dwRef);
 }
 ULONG InternalRelease()
 {
#ifdef _DEBUG
  LONG nRef = _ThreadModel::Decrement(&m_dwRef);
  if (nRef < -(LONG_MAX / 2))
  {
   ATLASSERT(0 && _T("Release called on a pointer that has already been released"));
  }
  return nRef;
#else
  return _ThreadModel::Decrement(&m_dwRef);
#endif
 }

 HRESULT _AtlInitialConstruct()
 {
  return m_critsec.Init();
 }
 void Lock() {m_critsec.Lock();}
 void Unlock() {m_critsec.Unlock();}
private:
 _AutoDelCritSec m_critsec;
};

 

CComObjectRootEx handles object reference count management for both nonaggregated and aggregated objects. It holds the object reference count if your object is not being aggregated, and holds the pointer to the outer unknown if your object is being aggregated. For aggregated objects, CComObjectRootEx methods can be used to handle the failure of the inner object to construct, and to protect the outer object from deletion when inner interfaces are released or the inner object is deleted.

 

CComObjectRootex處理對象引用計數管理：無聚合與聚合。非聚合：保存對象引用計數；聚合：保存外部unknown的指針。對應聚合對象來說，CComOBjectRooex方法被用來處理內部對象的錯誤來創建並保護不被外部對象刪除，當內部接口被釋放或內部對象被刪除時。