AcDbObject：经常被覆盖的函数

自定义类通常会重写以下函数：

virtual Acad::ErrorStatus 
audit(AcDbAuditInfo* pAuditInfo);
 
// Commonly useful, as this happens at a point where a new
// object state is being committed.
//
virtual Acad::ErrorStatus subClose();
 
// The next two functions apply to container objects. 
//
virtual Acad::ErrorStatus 
deepClone(AcDbObject* pOwnerObject,
          AcDbObject*& pClonedObject,
          AcDbIdMapping& idMap,
          Adesk::Boolean isPrimary = true) const;
 
virtual Acad::ErrorStatus 
wblockClone(AcRxObject* pOwnerObject,
            AcDbObject*& pClonedObject,
            AcDbIdMapping& idMap,
            Adesk::Boolean isPrimary = true) const;