public abstract void VisitConcreteElementA(ConcreteElementA element);
public override void VisitConcreteElementA(ConcreteElementA element) { Console.WriteLine("{0}被{1}访问", element.GetType().Name, this.GetType().Name); }
public abstract void VisitConcreteElementA(ConcreteElementA element);
public override void VisitConcreteElementA(ConcreteElementA element) { Console.WriteLine("{0}被{1}访问", element.GetType().Name, this.GetType().Name); }