与FileSystemWatcher的统一

Question

我正在尝试设置一个FileSystemWatcher，当文件更新时，我需要更改对象的颜色。

代码中没有错误，但结果是不执行操作。如果我使用void Start()，我可以改变对象的颜色。但是，只有在所需位置发生更改时，我才需要运行代码。

    using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System.IO;

public class ObjColorScript : MonoBehaviour
{
    public Color myColor;
    public MeshRenderer myRenderer;


    // Start is called before the first frame update
     void Start()
    {
        string path = @"B:\";
        MonitorDirectory(path);


        ///// New Added
        var fileSystemWatcher = new FileSystemWatcher();
        fileSystemWatcher.Path = @"B:\";
        fileSystemWatcher.Changed += FileSystemWatcher_Changed;
        fileSystemWatcher.EnableRaisingEvents = true;
    }


    ///// New Added
     void FileSystemWatcher_Changed(object sender, FileSystemEventArgs e)
    {
        myRenderer = GetComponent<MeshRenderer>();
        myRenderer.material.color = Color.green;
    }




    // Update is called once per frame
    void Update()
    {
        //myRenderer = GetComponent<MeshRenderer>();
        //myRenderer.material.color = Color.green;
    }

}

Answer 1

我遇到了一个类似的问题，我想在更改时调用一个方法，但它不会被调用。我相信这与Unity run循环外部调用的事件有关？

无论如何，对我来说，在更改时设置一个布尔标志并从Update()中调用实际的方法是很有帮助的

using System.IO;
using UnityEngine;

public class MyFileWatcher : MonoBehaviour
{
    [SerializeField] private string path;
    [SerializeField] private string file;
    private bool changed;
    private FileSystemWatcher watcher;


    private void OnEnable()
    {
        if (!File.Exists(Path.Combine(path, file)))
        {
            return;
        }

        watcher = new FileSystemWatcher();
        watcher.Path = path;
        watcher.Filter = file;

        // Watch for changes in LastAccess and LastWrite times, and
        // the renaming of files or directories.
        watcher.NotifyFilter = NotifyFilters.LastWrite;

        // Add event handlers
        watcher.Changed += OnChanged;

        // Begin watching
        watcher.EnableRaisingEvents = true;
    }


    private void OnDisable()
    {
        if(watcher != null)
        {
            watcher.Changed -= OnChanged;
            watcher.Dispose();
        }
    }


    private void Update()
    {
        if (changed)
        {
            // Do something here…
            changed = false;
        }
    }


    private void OnChanged(object source, FileSystemEventArgs e)
    {
        changed = true;
    }

}