c# - 新关键词混淆

Question

全部 -

阅读了有关新关键字及其使用时间的各种文章:

MSDN - http://msdn.microsoft.com/en-us/library/6fawty39(v=vs.80).aspx

StackOverflow - benefit of using new keyword in derived class member having same name with base class member

这是我为实践这个概念而编写的示例代码

    static void Main(string[] args)
    {
        Animal a2 = new Dog();
        a2.Talk();
        a2.Sing();
        a2.Greet();
        a2.Dance();
        Console.ReadLine();
    }

class Animal
{
    public Animal()
    {
        Console.WriteLine("Animal constructor");
    }

    public void Talk()
    {
        Console.WriteLine("Animal is Talking");
    }

    public virtual void Sing()
    {
        Console.WriteLine("Animal is Singing");
    }

    public void Greet()
    {
        Console.WriteLine("Animal is Greeting");
    }

    public virtual void Dance()
    {
        Console.WriteLine("Animal is Dancing");
    }
}

//Derived Class Dog from Animal
class Dog : Animal
{
    public Dog()
    {
        Console.WriteLine("Dog Constructor");
    }

    public new void Talk()
    {
        Console.WriteLine("Dog is Talking");
    }

    public override void Sing()
    {
        //base.Sing();
        Console.WriteLine("Dog is Singing");
    }

    public new void Dance()
    {
        Console.WriteLine("Dog is Dancing");
    }
}

我的任何输出如下:

让我感到困惑的是，通过在派生类中使用 new 关键字实际上显示了基类的输出。是不是错了 - 新关键字不应该隐藏基类成员资格，因此不应打印 Animal is Talking 和 Animal is Dancing 的结果。

谢谢

Answer 1

"new"意味着该方法是"new"而不是“覆盖”。因此，如果您从基类中调用该名称的方法，它不会被覆盖，因此不会调用派生类。