FileSystemwatcher获取文件列表

Question

我一直在关注这里的指导FileSystemWatcher Changed event is raised twice。

但是我有一个我正在看的文件列表，如果我一起删除了20个文件，这个事件被称为20次。这是预料之中，并正常工作。

我怎么只能有一个事件20“同时”文件更改（即我怎么能忽略所有其他文件的更改，直到低于Onchanged一审代码已经完成。现在Onchanged被称为20次触发一次）？

private void Main_Load(object sender, EventArgs e) 
{ 
    public static List<FileSystemWatcher> watchers = new List<FileSystemWatcher>(); 
    UpdateWatcher(); 
} 


public void OnChanged(object sender, FileSystemEventArgs e) 
{ 
    try 
    { 
     Logging.Write_To_Log_File("Item change detected " + e.ChangeType + " " + e.FullPath + " " + e.Name, MethodBase.GetCurrentMethod().Name, "", "", "", "", "", "", 2); 
     watchers.Clear(); 

     foreach (FileSystemWatcher element in MyGlobals.watchers) 
     { 
     element.EnableRaisingEvents = false; 
     } 

     //Do some processing on my list of files here.... 
     return; 

    }  
    catch (Exception ex) 
    { 
     // If exception happens, it will be returned here 
    }     
    finally 
    { 
     foreach (FileSystemWatcher element in MyGlobals.watchers) 
     { 
      element.EnableRaisingEvents = true; 
     } 
    } 
} 





public void UpdateWatcher() // Check Items 
     { 

     try 
     { 
     watchers.Clear(); 

     for (int i = 0; i < MyGlobals.ListOfItemsToControl.Count; i++) // Loop through List with for 
     { 
     FileSystemWatcher w = new FileSystemWatcher(); 
     w.Path = Path.GetDirectoryName(MyGlobals.ListOfItemsToControl[i].sItemName); // File path  
     w.Filter = Path.GetFileName(MyGlobals.ListOfItemsToControl[i].sItemName); // File name 
     w.Changed += new FileSystemEventHandler(OnChanged); 
     w.Deleted += new FileSystemEventHandler(OnChanged); 
     w.Created += new FileSystemEventHandler(OnChanged); 
     w.EnableRaisingEvents = true; 
     watchers.Add(w); 
     } 
     } 
     catch (Exception ex) 
     { 
     // If exception happens, it will be returned here 

     } 
     } 

Answer 1

这里的关键是“一起”对你意味着什么。毕竟系统对每个系统都进行了独立的删除操作，这在技术上意味着它们并不全部在同一时间被删除，但是如果你只是想关闭，让我们说，如果它们都在5秒内被删除，那么我们只想让OnChange触发一次，你可以做到以下几点。请注意，这不处理重命名更改通知。你没有听它，所以我认为你不需要。

根据您的使用情况，您可能需要将5秒窗口更改为小窗口。

class SlowFileSystemWatcher : FileSystemWatcher 
    { 
     public delegate void SlowFileSystemWatcherEventHandler(object sender, FileSystemEventArgs args); 

     public event SlowFileSystemWatcherEventHandler SlowChanged; 
     public DateTime LastFired { get; private set; } 

     public SlowFileSystemWatcher(string path) 
      : base(path) 
     { 
      Changed += HandleChange; 
      Created += HandleChange; 
      Deleted += HandleChange; 
      LastFired = DateTime.MinValue; 
     } 

     private void SlowGeneralChange(object sender, FileSystemEventArgs args) 
     { 
      if (LastFired.Add(TimeSpan.FromSeconds(5)) < DateTime.UtcNow) 
      { 
       SlowChanged.Invoke(sender, args); 
       LastFired = DateTime.UtcNow; 
      } 
     } 

     private void HandleChange(object sender, FileSystemEventArgs args) 
     { 
      SlowGeneralChange(sender, args); 
     } 

     protected override void Dispose(bool disposing) 
     { 
      SlowChanged = null; 
      base.Dispose(disposing); 
     } 
    }