如何使用枚举作为布尔标志？

Question

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

public class SceneFader : MonoBehaviour
{
    public CanvasGroup canvasGroup;
    public bool fadeAutomatically;
    public float fadeTime;
    // Stores the currently running routine to be able to stop/cancel it
    private Coroutine _currentRoutine;
    // Stores the current direction
    private bool _currentDirection;
    // Used for the automatic switch to determine the next direction
    private bool _nextDirection;

    private void Start()
    {  
            SceneManager.sceneLoaded += SceneManager_sceneLoaded;
    }

    public enum FadeDirection
    {
        In,
        Out
    }

    public IEnumerator FadeAndLoadScene(bool fadeDirection, string sceneToLoad)
    {
        yield return Fade(canvasGroup, fadeDirection, false);

        SceneManager.LoadSceneAsync(sceneToLoad);
    }
    private void SceneManager_sceneLoaded(Scene arg0, LoadSceneMode arg1)
    {
        if (MenuController.LoadSceneForSavedGame == true)
        {
            var saveLoad = GameObject.Find("Save System").GetComponent<SaveLoad>();
            saveLoad.Load();
        }
    }

    private void StartFade(bool isIn, bool autoSwitch)
    {
        // Another routine running already?
        if (_currentRoutine != null)
        {
            // Different direction?
            if (_currentDirection != isIn)
            {
                // Interrupt the current routine
                StopCoroutine(_currentRoutine);

                // And start a new one
                _currentRoutine = StartCoroutine(Fade(canvasGroup, isIn, autoSwitch));
            }
        }
        else
        {
            // Otherwise directly start the first routine
            _currentRoutine = StartCoroutine(Fade(canvasGroup, isIn, autoSwitch));
        }
    }

    private void Update()
    {
        if (!fadeAutomatically)
        {
            if (Input.GetKeyDown(KeyCode.O))
            {
                StartFade(false, fadeAutomatically);
            }

            if (Input.GetKeyDown(KeyCode.I))
            {
                StartFade(true, fadeAutomatically);
            }
        }
        else // fadeAutomatically
        {
            StartFade(_nextDirection, fadeAutomatically);
        }
    }

    public IEnumerator Fade(CanvasGroup canvasGroup, bool isIn, bool autoSwitch)
    {
        // Store the current fading direction
        _currentDirection = isIn;

        // Determine start and end value depending on the fading direction
        var startValue = isIn ? 0 : 1;
        var targetValue = isIn ? 1 : 0;

        // Get the so far elapsed time according to the current alpha
        // It is the fadeTime multiplied by the already added or removed alpha
        var elapsedTime = fadeTime * (isIn ? canvasGroup.alpha : (1 - canvasGroup.alpha));
        while (elapsedTime <= fadeTime)
        {
            // Use Maths.Lerp to linear interpolate between the start and end value
            canvasGroup.alpha = Mathf.Lerp(startValue, targetValue, elapsedTime / fadeTime);

            // For "skipping" one single frame you can simply return null
            yield return null;

            elapsedTime += Time.deltaTime;
        }

        // To be sure to end with clean values
        canvasGroup.alpha = targetValue;

        // Should we automatically switch the direction?
        if (autoSwitch) _nextDirection = !isIn;

        // Reset the current routine (see below)
        // Not sure if this is really necessary, I believe it will reset anyway 
        // as soon as the routine has finished .. but just to be sure
        _currentRoutine = null;
    }   
}

我添加了这个枚举并使用它：第 24 到 32 行

public enum FadeDirection
    {
        In,
        Out
    }

    public IEnumerator FadeAndLoadScene(bool fadeDirection, string sceneToLoad)
    {
        yield return Fade(canvasGroup, fadeDirection, false);

然后在像这样的其他脚本中使用它：

StartCoroutine(sceneFader.FadeAndLoadScene(SceneFader.FadeDirection.In, _newGameButtonLevel));

但我收到错误：

SceneFader.FadeDirection.In

无法从 SceneFader.FadeDirection 转换为 bool

我也想使用淡入淡出脚本来加载场景。尝试使用枚举对其进行扩展，但出现此错误。

主要目标是能够在加载场景时淡入/淡出，如果只是需要淡入某些场景，还可以在游戏中淡入。

Answer 1

你想做什么可以考虑extension methods。 您可以使用以下功能增强枚举：

public enum Direction {
     north,
     east,
     south,
     west
}

public static class DirectionExtension {
    public static Direction opposite(this Direction dir) {
        return (int)dir < 2 ? (dir + 2) : (dir - 2);
    }

    public static Direction previous(this Direction dir) {
        return dir == Direction.north ? Direction.west : dir - 1;
    }

    public static Direction next(this Direction dir) {
        return dir == Direction.west ? Direction.north : dir + 1;
    }
}

对于您的情况，尽管您可以在代码中的任何位置比较枚举实例的值，但您可以执行以下操作：

public enum FadeDirection {
    In,
    Out
}

public static class FadeDirectionExtension {
    public static bool In(this FadeDirection fadeDir) {
        return fadeDir == FadeDirection.In;
    }

    public static bool Out(this FadeDirection fadeDir) {
        return fadeDir == FadeDirection.Out;
    }
}