Question

我希望这不是一个愚蠢的问题，但我无法弄明白。

我有一个准系统游戏类：

public class Game1 : Game
{
    GraphicsDeviceManager graphics;
    SpriteBatch spriteBatch;
    String inputHolder;

    public Game1()
        : base()
    {
        graphics = new GraphicsDeviceManager(this);
        Content.RootDirectory = "Content";

        inputHolder = "Enter your keys: ";
    }

    protected override void Initialize()
    {
        base.Initialize();


        InputManager.stringToUpdate = inputHolder;

    }
    protected override void LoadContent()
    {
        spriteBatch = new SpriteBatch(GraphicsDevice);
    }

    protected override void UnloadContent()
    {
    }

    protected override void Update(GameTime gameTime)
    {
        if (Keyboard.GetState().IsKeyDown(Keys.Escape))
        {
            Exit();
        }
        base.Update(gameTime);

        InputManager.update(Keyboard.GetState());
    }

    protected override void Draw(GameTime gameTime)
    {
        GraphicsDevice.Clear(Color.CornflowerBlue);

        base.Draw(gameTime);

        Console.WriteLine(inputHolder);
    }
}

我还有一个InputManager类：

static class InputManager
{
    public static string stringToUpdate;

    public static void update(KeyboardState kbState)
    {
        if (stringToUpdate != null)
        {
            foreach (Keys k in kbState.GetPressedKeys())
            {
                stringToUpdate += k.ToString();
            }
        }
    }
}

然而，无论我按什么键，我都按原始字符串inputHolder不受影响，即使字符串在C＃中被视为引用类型。

我试过改变 InputManager.stringToUpdate = inputHolder; 至 InputManager.stringToUpdate = ref inputHolder; 没有任何反应。

我在这里缺少什么？

Answer 1

正如已经说过的，字符串是不可变的。将inputHolder字符串包装在一个类中将为您提供所需的效果：

public class InputHolder
{
    public string Input { get; set; }
}

public class Game1 : Game
{
    GraphicsDeviceManager graphics;
    SpriteBatch spriteBatch;
    InputHolder inputHolder = new InputHolder();

    public Game1()
        : base()
    {
        graphics = new GraphicsDeviceManager(this);
        Content.RootDirectory = "Content";

        inputHolder.Input = "Enter your keys: ";
    }

    protected override void Initialize()
    {
        base.Initialize();
        InputManager.inputHolderToUpdate = inputHolder;
    }

    // etc

    protected override void Draw(GameTime gameTime)
    {
        GraphicsDevice.Clear(Color.CornflowerBlue);
        base.Draw(gameTime);
        Console.WriteLine(inputHolder.Input);
    }
} 

static class InputManager
{
    public static InputHolder inputHolderToUpdate;

    public static void update(KeyboardState kbState)
    {
        if (inputHolderToUpdate != null)
        {
            foreach (Keys k in kbState.GetPressedKeys())
            {
                inputHolderToUpdate.Input = inputHolderToUpdate.Input + k.ToString();
            }
        }
    }
}

根据按键更新字符串

1 个答案: