c# - 根据切换数组检查哪个切换已更改

Question

我定义了一个切换结构数组。我正在为每个人添加一个监听器。现在我想知道当用户按下切换按钮更改值时哪个切换按钮被更改。我如何从脚本中知道哪个切换已更改并将其用作索引？

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

public class ToggleData : MonoBehaviour {

    [System.Serializable]
    public struct toggleInfo {
        public Toggle toggle;
        public TextMeshProUGUI toggleText;
    }

    public toggleInfo[] toggles;

    public int toggleIndex = 0;

    // Start is called before the first frame update
    void Start () {

        for (int i = 0; i < toggles.Length; i++) {
            toggles[i].toggle.onValueChanged.AddListener (delegate {
                ToggleValueChanged (toggles[i].toggle);
            });
        }

    }

    void ToggleValueChanged (Toggle change) {
        Debug.Log ("toggle changed " + toggleIndex); //Get the index here
    }
}

Answer 1

你可以例如使用

for (int i = 0; i < toggles.Length; i++) 
{
    // Due to variable capturing in Linda expresions you have to store 
    // each value of i in a new variable
    // See https://learn.microsoft.com/dotnet/csharp/language-reference/operators/lambda-expressions#capture-of-outer-variables-and-variable-scope-in-lambda-expressions
    // and e.g. https://stackoverflow.com/questions/271440/captured-variable-in-a-loop-in-c-sharp
    var index = i;
    toggles[index].toggle.onValueChanged.AddListener (() => ToggleValueChanged (toggles[index].toggle, index));
}

还有

void ToggleValueChanged (Toggle change, int index) 
{
    Debug.Log ("toggle changed " + index);
}

---

或者不使用struct，而是使用class

public class toggleInfo { ... }

并使用

for (int i = 0; i < toggles.Length; i++) 
{
    // Due to variable capturing in Linda expresions you have to store 
    // each value of i in a new variable
    // See https://learn.microsoft.com/dotnet/csharp/language-reference/operators/lambda-expressions#capture-of-outer-variables-and-variable-scope-in-lambda-expressions
    // and e.g. https://stackoverflow.com/questions/271440/captured-variable-in-a-loop-in-c-sharp
    var index = i;
    toggles[index].toggle.onValueChanged.AddListener (() => ToggleValueChanged (toggles[index]));
}

还有

void ToggleValueChanged (toggleInfo info) 
{
    Debug.Log ("toggle changed " + Array.IndexOf(toggles, info));
}