在c#中从不同脚本访问实例[重复]

Question

这是我陷入的 OOP 问题。 假设我有这种情况 Player.cs：

public class Player
{
    int hp,armor;
    string nickName;
    public Player()
    {
        hp=3;
        armor=3;
        nickName="Unknown";
    }
    public void minusHP()
    {
        hp--;
    }
}

PlayerManager.cs

public class PlayerManager
{
    Player p = new Player();
}

TakeDMG.cs

public class TakeDMG
{
    //if event happens then : 
    p.minusHP();
}

如何从不同的脚本访问播放器实例并使用它，如何在另一个脚本中为它声明其他方法？

Answer 1

最好的方法是在你的其他脚本中获取玩家参考：

public class TakeDMG : MonoBehaviour
{
    //This is the player reference to set on editor mode
    public Player player;
}

或者，如果它不是MonoBehaviour，则在类的构造中传递它

如果不可能，您可以使用Singleton 模式。

这是我使用的一个例子（灵感来自here）：

public abstract class Singleton : MonoBehaviour
{
    public static bool Quitting { get; private set; }
    private void OnApplicationQuit()
    {
        Quitting = true;
    }

    private void OnDestroy()
    {
        Quitting = true;
    }
}

public class Singleton<T> : Singleton where T : MonoBehaviour
{
    /// <summary>
    /// Singleton instance
    /// </summary>
    protected static T instance;

    /// <summary>
    /// Access singleton instance through this propriety.
    /// </summary>
    public static T Instance
    {
        get
        {
            if (Quitting)
            {
                return null;
            }

            if (instance == null)
            {
                instance = FindObjectOfType<T>();
                DontDestroyOnLoad(instance.gameObject);
            }

            return instance;
        }
    }

    /// <summary>
    /// Awake the singleton -> add instance to the same gameobject than this class
    /// </summary>
    protected virtual void Awake()
    {
        if (instance == null)
        {
            instance = Instance;
            DontDestroyOnLoad(gameObject);
        }
        else
        {
            // We have already an instance, we destroy this one
            if(this != instance)
                Destroy(gameObject);
        }
    }
}

    public class SingletonInterface<T> : Singleton where T : MonoBehaviour
{
    /// <summary>
    /// Singleton instance
    /// </summary>
    protected static T instance;

    /// <summary>
    /// Access singleton instance through this propriety.
    /// </summary>
    protected static T Instance
    {
        get
        {
            if (Quitting)
            {
                return null;
            }

            if (instance == null)
            {
                instance = FindObjectOfType<T>();
                DontDestroyOnLoad(instance.gameObject);
            }

            return instance;
        }
    }

    /// <summary>
    /// Awake the singleton -> add instance to the same gameobject than this class
    /// </summary>
    protected virtual void Awake()
    {
        if (instance == null)
        {
            instance = Instance;
            DontDestroyOnLoad(gameObject);
        }
        else
        {
            // We have already an instance, we destroy this one
            if(this != instance)
                Destroy(gameObject);
        }
    }
}

您可以创建您的播放器管理器：

public class PlayerManager : Singleton<PlayerManager>
{
    public Player Player;
}

并访问它

public class OtherClass : MonoBehaviour
{
    public void SomeMethod()
    {
        PlayerManager.Instance.Player.minusHP();
    }
}

Answer 2

假设您的所有脚本都已附加到同一个播放器对象，则可以在任何脚本中使用gameObject 访问播放器对象。

从那里，您可以调用GetComponent<script class> 来获取另一个脚本的实例。

例如：

public class TakeDMG
{
    //if event happens then : 
    public void SomeEvent()
    {
        var p = gameObject.GetComponent<Player>();
        p.minusHP();
    }
}

请注意，还有优化的空间。对于 GetComponent 的这种“搜索”只能在每个脚本启动时使用一个字段进行一次。

public class TakeDMG
{
    Player player;   // private field to store the reference to Player script;

    public Start()
    {
        player = gameObject.GetComponent<Player>();
    }

    //if event happens then : 
    public void SomeEvent()
    {
        player.minusHP();
    }
}

当然这只能在播放器脚本从头附加到播放器对象的情况下才能做到，我想可能是这样的。

如果您必须在许多脚本上重复相同的代码（获取播放器实例），您可以使用继承来“分解”相同的代码。

public class PlayerScript
{
    protected Player player;   // field to store the reference to Player script;

    public virtual Start()
    {
        player = gameObject.GetComponent<Player>();
    }
}

// This scripts inherit from PlayerScript
public class TakeDMG : PlayerScript
{
    //if event happens then : 
    public void SomeEvent()
    {
        player.minusHP();
    }
}


// This one as well
public class AnotherScript : PlayerScript
{
    //if event happens then : 
    public void SomeOtherEvent()
    {
        player.minusHP();
    }
}