编辑代码

using System;
using System.Collections.Generic;
public class HelloWorld
{
    public static void Main()
    {
        List<DemoClass> fun = new List<DemoClass>{new DemoClass(),new Demo2Class(),new Demo3Class()};
        foreach (var item in fun)
         {
            item.Function();
         }
    }
}

public class DemoClass{
    public string className = "DemoClass";

    public virtual void  Function(){
            Console.WriteLine(className);
    }
}

public class Demo2Class : DemoClass{
    public override void Function(){        
            Console.WriteLine("Demo2Class");
    }
}
public class Demo3Class : DemoClass{
    public override void Function(){        
            Console.WriteLine("Demo3Class");
            base.Function();
    }
}