c# - 从 "base.base"类调用方法？

Question

“假设以下代码:

public class MultiplasHerancas
{
    static GrandFather grandFather = new GrandFather();
    static Father father = new Father();
    static Child child = new Child();

    public static void Test() 
    {
        grandFather.WhoAreYou();
        father.WhoAreYou();
        child.WhoAreYou();

        GrandFather anotherGrandFather = (GrandFather)child;
        anotherGrandFather.WhoAreYou(); // Writes "I am a child"
    }

}

public class GrandFather
{
    public virtual void WhoAreYou() 
    {
        Console.WriteLine("I am a GrandFather");
    }
}

public class Father: GrandFather
{
    public override void WhoAreYou()
    {
        Console.WriteLine("I am a Father");
    }
}

public class Child : Father 
{
    public override void WhoAreYou()
    {
        Console.WriteLine("I am a Child");

    }
}

我想从“ child ”对象打印“我是祖父”。

我如何让子对象在“base.base”类上执行方法？我知道我可以执行基本方法(它会打印“我是父亲”)，但我想打印“我是祖父”!如果有办法做到这一点，是否在 OOP 设计中推荐？

注意:我不使用/将要使用这种方法，我只是想加强知识传承。

Answer 1

这只能使用 Method Hiding 才能实现-

public class GrandFather
{
    public virtual void WhoAreYou()
    {
        Console.WriteLine("I am a GrandFather");
    }
}

public class Father : GrandFather
{
    public new void WhoAreYou()
    {
        Console.WriteLine("I am a Father");
    }
}

public class Child : Father
{
    public new void WhoAreYou()
    {
        Console.WriteLine("I am a Child");            
    }
}

然后这样调用它-

Child child = new Child();
((GrandFather)child).WhoAreYou();

使用new关键字在派生类中隐藏基类的继承成员。