C# 继承的笔记

using System;
class Car
{
    public  int Odometer = 0;
    public virtual void MoveForward()
    {
        Console.WriteLine("Moving Forwards");
        Odometer += 2;
        Console.WriteLine("Odometer reading :{0}", Odometer);
    }
}

class RacingCar : Car
{
    public override void MoveForward()
    {
        Console.WriteLine("Moving Dangerously fast forwards");
        Odometer += 30;
        Console.WriteLine("Odometer in racing car:{0}", Odometer);
    }
}
public static class Program
{
    public static void Main()
    {
        Car myCar = new Car();
        myCar.MoveForward();
        RacingCar myRacingCar = new RacingCar();
        myRacingCar.MoveForward();
        Console.WriteLine(myCar.Odometer);
    }
} 

public Odometer  都可以编译

private Odometer         myRacingCar.MoveForward(); Console.WriteLine(myCar.Odometer); 无法编译

protected Odometer   Console.WriteLine(myCar.Odometer); 无法编译

internal Odometer 都可以编译

internal protected Odometer 都可以编译