c# - 初学者，用 C# 制作基于控制台的 RPG 但有问题

Question

以下是我目前所拥有的:玩家可以输入诸如北、东、南、西和帮助之类的命令，并且它可以工作。当我执行 Look 命令时，我的问题就出现了。我记录了当前房间的描述，但它永远不会改变。我相信，问题可能与那些神秘的引用和值类型有关，但我没有足够的经验来确定，或者如何解决它。
然而 ，当我把 Console.WriteLine(CurrentRoom.RoomDescription) 放在任何 currentRoom.SetCurrentRoom(rooms, player) 下时，它工作得很好。

主要类:

class Program
{
    static void Main(string[] args)
    {
        Room currentRoom;
        List<Room> rooms = new List<Room>();
        Player player = new Player();

        //Rooms
        Room startingRoom = new Room("Starting room", "This is the starting room", 0, 0);
        Room northRoom = new Room("North room", "This is the north room", 0, 1);
        Room eastRoom = new Room("East room", "This is the east room", 1, 0);
        Room southRoom = new Room("South room", "This is the south room", 0, -1);
        Room westRoom = new Room("West room", "This is the west room", -1, 0);

        //Add and set starting room as current room
        rooms.Add(startingRoom);
        currentRoom = startingRoom;

        //Adding rooms
        rooms.Add(northRoom);
        rooms.Add(eastRoom);
        rooms.Add(southRoom);
        rooms.Add(westRoom);

        Console.WriteLine("Welcome to the Dungeon. This is the starting room.");
        GetHelp();
        Console.WriteLine("There are four exits. Which way do you want to go?");
        while (true)
        {
            HandleInput(player, currentRoom, rooms);
        }



    }

    private static void GetHelp()
    {
        Console.WriteLine("You can move to locations by entering 'North', 'East', 'South', and 'West'.");
        Console.WriteLine("You can also examine the room by entering 'Look'.");
        Console.WriteLine("Type 'Help' at any time to view instructions.");
    }

    private static Room SetCurrentRoom(List<Room> rooms, Player player)
    {
        foreach (var room in rooms)
        {
            if (room.XPos == player.PlayerXPos && room.YPos == player.PlayerYPos)
            {
                return room;
            }

        }
        Console.WriteLine("Invalid direction.");

        return null;

    }

    private static void HandleInput(Player player, Room currentRoom, List<Room> rooms)
    {
        var input = Console.ReadLine();
        if (input == "North")
        {
            player.Move(Direction.Directions.North);
            currentRoom = SetCurrentRoom(rooms, player);


        }
        else if (input == "East")
        {
            player.Move(Direction.Directions.East);
            currentRoom = SetCurrentRoom(rooms, player);


        }
        else if (input == "South")
        {
            player.Move(Direction.Directions.South);
            currentRoom = SetCurrentRoom(rooms, player);


        }
        else if (input == "West")
        {
            player.Move(Direction.Directions.West);
            currentRoom = SetCurrentRoom(rooms, player);

        }
        else if (input == "Help")
        {
            GetHelp();
        }
        else if (input == "Look")
        {
            Console.WriteLine(currentRoom.RoomDescription);
        }
        else
        {
            Console.WriteLine("Invalid input.");
        }

    }
}

房间等级:

public class Room
{
    public string RoomName { get; set; }
    public string RoomDescription { get; set; }
    public int XPos { get; set; }
    public int YPos { get; set; }

    public Room(string roomName, string roomDescription, int xPos, int yPos)
    {
        this.RoomName = roomName;
        this.RoomDescription = roomDescription;
        this.XPos = xPos;
        this.YPos = yPos;

    }
}

球员等级:

public class Player
{
    public int Health { get; set; }
    public string Name { get; set; }
    public int PlayerXPos { get; set; }
    public int PlayerYPos { get; set; }

    public void Move(Direction.Directions direction)
    {
        switch (direction)
        {
            case Direction.Directions.North:
                PlayerYPos += 1;
                Console.WriteLine("Moving north");
                break;
            case Direction.Directions.East:
                PlayerXPos += 1;
                Console.WriteLine("Moving east.");
                break;
            case Direction.Directions.South:
                PlayerYPos -= 1;
                Console.WriteLine("Moving south.");
                break;
            case Direction.Directions.West:
                PlayerXPos -= 1;
                Console.WriteLine("Moving west.");
                break;

        }
    }


}

方向类:

public class Direction
{
    public enum Directions
    {
        North,
        East,
        South,
        West
    }
}

我是初学者，所以代码可能会让有经验的程序员反感。

Answer 1

I believe, the problem may have to do with those mystical reference and value types

你很亲近。问题是因为currentRoom传递给 HandleInput方法“按值”而不是“按引用”，但您正在尝试分配不同的 Room到它。

您的签名HandleInput方法是这样的:

private static void HandleInput(Player player, Room currentRoom, List<Room> rooms)

在您尝试设置的方法中 currentRoom到另一个 Room .

但是默认情况下，当某些东西传递给方法时，它是“按值”传递的，这意味着您可以更改该变量的属性，但不能更改 实际它所指的变量 - 就像 currentRoom = SetCurrentRoom(rooms, player); - 除非你通过“引用”传递它，像这样:

private static void HandleInput(Player player, ref Room currentRoom, List<Room> rooms)

在这种情况下，您必须像这样调用它:

HandleInput(player, ref currentRoom, rooms);

什么ref关键字的意思是你调用的方法可以改变值类型currentRoom的“底层对象”指。