相关疑难解决方法(0)

我有两节课:

/*Switch.h*/
    class CSwitch : public CDeviceEntity {}
/*EndSystem.h*/
    class CEndSystem : public CDeviceEntity {}

但是当我使用时:

CDeviceEntity* dev = NULL;
dev = topo->headList[i]->node;
if ( DYNAMIC_DOWNCAST( CEndSystem, dev ) != NULL ) {}

" DYNAMIC_DOWNCAST"总是返回not NULL而dev是一种class CEndSystem或者class CSwitch.

如果使用:

/*Switch.h*/
    class CSwitch : public CDeviceEntity { DECLARE_DYNAMIC(CSwitch) } 
    and
/*Switch.cpp*/
    IMPLEMENT_DYNAMIC(CSwitch, CDeviceEntity)
/*EndSystem.h*/
    class CEndSystem : public CDeviceEntity { DECLARE_DYNAMIC(CEndSystem) }
    and
/*EndSystem.cpp*/
    IMPLEMENT_DYNAMIC(CEndSystem, CDeviceEntity)

" DYNAMIC_DOWNCAST"返回NULL或not NULL根据 …