面向对象之abstract

    public abstract class FirstAbstractClass
    {
        //抽象类中，可以包括非抽象方法
        public void SayHi()
        {
            Console.WriteLine("The object Method in Abstract Class!");
        }

        //抽象方法只能在抽象类中声明，抽象方法没有方法体
        public abstract void FirstAbs();
    }

    public abstract class SecondAbstractClass : FirstAbstractClass
    {
        public abstract void SecondAbsMethod();
    }

    public class ThirdClass:SecondAbstractClass
    {
        public override void SecondAbsMethod()
        {
            throw new NotImplementedException();
        }

        public override void FirstAbs()
        {
            throw new NotImplementedException();
        }
    }
    public interface myinterface
    {
        void InterfaceMehtod();
    }