代码 C# 有问题

Question

This is simple console app for rent rooms. I have a problem with method Bill, it's always 0 when I test app. I multiple number of reserve days with price of room but somethig is wrong. Can someone help me?

static void Main(string[] args)
    {
        Room RoomOne = new Room(11, 1, 6, false);
        Room RoomTwo = new Room(21, 2, 5, false);
        Room RoomThree = new Room(31, 3, 9, true);
        Customer CustomerOne = new Customer("Bob Marley", "Male", 39, 1);
        Customer CustomerTwo = new Customer("Isaac Newton", "Male", 67, 2);
        Customer CustomerThree = new Customer("Frankenstein", "Male", 50, 3);
        Console.WriteLine("");
        CustomerOne.ReserveRoom();
        RoomOne.IsRoomOccupied();
        Console.WriteLine("");
        CustomerTwo.ReserveRoom();
        RoomTwo.IsRoomOccupied();
        Console.WriteLine("");
        CustomerThree.ReserveRoom();
        RoomThree.IsRoomOccupied();
        Console.ReadKey();
    }

class Customer : Room
{
    private string Name;
    private string Gendre;
    private int Age;
    private int ID;

    public Customer()
    {
    }

    public Customer(string name, string gendre, int age, int id)
    {
        Name = name;
        Gendre = gendre;
        Age = age;
        ID = id;
    }

    public void ReserveRoom()
    {
        Console.WriteLine("Welcome to Plaza Hotel!!!\nWhat kind of room would you like? We have Standard, Moderate and Superior.");
        string roomtype = Console.ReadLine();

        switch (roomtype)
        {
            case "Standard":
                    {
                        Standard RoomOne = new Standard();
                    }
                    break;
            case "Moderate":
                    {
                        Standard RoomTwo = new Standard();
                    }
                    break;
            case "Superior":
                    {
                        Standard RoomThree = new Standard();
                    }
                    break;
            default:
                {
                    Console.WriteLine("That type of room doesn't exist!!!");
                }
                break;
        }
    }
}

 class Room
{
    private int RoomNumber;
    private int FloorNumber;
    private double Price;
    private int NumberOfDaysOccupied;
    private bool Occupied = false;
    private string TypeOfRoom;

    public Room()
    {

    }
    public Room(int room, int floor,int nodo, bool occupied)
    {
        RoomNumber = room;
        FloorNumber = floor;
        NumberOfDaysOccupied = nodo;
        Occupied = occupied;
    }

    public void NumberOfRoom()
    {
        Console.WriteLine("Room number is: {0}", RoomNumber);
    }

    public void NumberOfFloor()
    {
        Console.WriteLine("Floor number is: {0}", FloorNumber);
    }

    public double Bill()
    {
        return NumberOfDaysOccupied * Price;
    }

    public void IsRoomOccupied()
    {
        if (Occupied == true)
        {
            Console.WriteLine("This type of room is occupied!!!");
        }
        else
        {
            Console.WriteLine("Your room number is: {0} on floor: {1}, reserve for: {2} and your bill is: {3}" ,RoomNumber, FloorNumber, NumberOfDaysOccupied, Bill());
        }
    }

    public class Standard : Room
    {
        public Standard()
        {
            Price = 50;
            TypeOfRoom = "Standard";
        }
    }

    public class Moderate : Room
    {
        public Moderate()
        {
            Price = 100;
            TypeOfRoom = "Moderate";
        }
    }

    public class Superior : Room
    {
        public Superior()
        {
            Price = 200;
            TypeOfRoom = "Superior";
        }
    }
}

Answer 1

Your Standard/Moderate/Superior classes inherit Room, but do not call the constructor on Room that sets the price. When you don't provide the base class constructor to call, the default constructor will be called, which doesn't set any of the options.

You'll need to update your rooms to be more like:

public class Standard : Room
{
    public Standard(int room, int floor, int nodo, bool occupied)
        : base(room, floor, nodo, occupied)
    {
        Price = 50;
        TypeOfRoom = "Standard";
    }
}

Then setup your rooms like:

Room standardRoom = new Standard(11, 1, 6, false);