我有这样的公共(public)接口(interface)层次结构:structISwitchable{/*Obtainpointertoanotherimplementedinterfaceofthesameinstance.*/virtualintswitch(unsignedintinterfaceId,void**pInstance)=0;};structIFoo:publicISwitchable{/*Methods*/};structIBar:publicISwitchable{/*Methods*/};structIFooBar:publicIFoo,publicIBar{