1.封装
2.继承
3.多态
不扯别的，看代码就好…

using System;
//程序的声明
namespace demo0709
{//类名class Program{//主程序的入口static void Main(string[] args){//多态性Transport transport = new Bus();transport.reduceSpeed();transport.increaseSpeed();Console.ReadKey();}}//交通工具类class Transport{private int id;private string name;public Transport(){}public Transport(int id, string name){this.id = id;this.name = name;}public override string ToString(){return this.id+"----"+this.name;}//车类有2个方法public virtual void reduceSpeed() => Console.WriteLine("减速慢行");public virtual void increaseSpeed() => Console.WriteLine("高速路段请加速");}//Bus类class Bus:Transport{//重写父类的方法public override void reduceSpeed() => Console.WriteLine("减速啦~~biubiu---");public override void increaseSpeed() => Console.WriteLine("加速啦~~~biubiu---");}
}

来，破而后立！

看报错提示，自己领悟~