c#继承中的函数调用

首先看下面的代码:

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using System;
 
namespace Test
{
    public class Base
    {
        public void Print()
        {
            Console.WriteLine(Operate(8, 4));
        }
 
        protected virtual int Operate(int x, int y)
        {
            return x + y;
        }
    }
}
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namespace Test
{
    public class OnceChild : Base
    {
        protected override int Operate(int x, int y)
        {
            return x - y;
        }
    }
}
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namespace Test
{
    public class TwiceChild : OnceChild
    {
        protected override int Operate(int x, int y)
        {
            return x * y;
        }
    }
}
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namespace Test
{
    public class ThirdChild : TwiceChild
    {
    }
}
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namespace Test
{
    public class ForthChild : ThirdChild
    {
        protected new int Operate(int x, int y)
        {
            return x / y;
        }
    }
}
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namespace Test
{
    class Program
    {
        static void Main(string[] args)
        {
            Base b = null;
            b = new Base();
            b.Print();
            b = new OnceChild();
            b.Print();
            b = new TwiceChild();
            b.Print();
            b = new ThirdChild();
            b.Print();
            b = new ForthChild();
            b.Print();
        }
    }
}

看结果:

c#继承中的函数调用

从结果中可以看出:使用override重写之后,调用的函数是派生的最远的那个函数,使用new重写则是调用new之前的派生的最远的函数,即把new看做没有重写似的。