本文目录
- 使用filesystemwatcher时怎么处理大文件
- FileSystemWatcher怎么动态创建和监测多个文件夹
- filesystemwatcher组件事件不触发
- c# filesystemwatcher 监控文件是否写完
- C# FileSystemWatcher组件
- c# 中的FileSystemWatcher问题
- C#用filesystemwatcher监控文件夹变化时，怎样监控到被监控的文件夹本身变化
- c#FileSystemWatcher如何监视【远程计算机】文件，非本地计算机，谢谢！
使用filesystemwatcher时怎么处理大文件
使用filesystemwatcher时怎么处理大文件 FileSystemWatcher基础属性：Path——这个属性告诉FileSystemWatcher它需要监控哪条路径。例如，如果我们将这个属性设为“C:\test”，对象就监控test目录下所有文件发生的所有改变（包括删除，修改，创建，重命名）。IncludeSubDirectories——这个属性说明FileSystemWatcher对象是否应该监控子目录中（所有文件）发生的改变。Filter——这个属性允许你过滤掉某些类型的文件发生的变化。例如，如果我们只希望在TXT文件被修改/新建/删除时提交通知，可以将这个属性设为“*txt”。在处理高流量或大型目录时，使用这个属性非常方便。NotifyFilter——获取或设置要监视的更改类型。可以进一步的过滤要监控的更改类型，如watcher.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite| NotifyFilters.FileName | NotifyFilters.DirectoryName;事件：Changed——当被监控的目录中有一个文件被修改时，就提交这个事件。值得注意的是，这个事件可能会被提交多次，即使文件的内容仅仅发生一项改变。这是由于在保存文件时，文件的其它属性也发生了改变。Created——当被监控的目录新建一个文件时，就提交这个事件。如果你计划用这个事件移动新建的事件，你必须在事件处理器中写入一些错误处理代码，它能处理当前文件被其它进程使用的情况。之所以要这样做，是因为Created事件可能在建立文件的进程释放文件之前就被提交。如果你没有准备正确处理这种情况的代码，就可能出现异常。Deleted——当被监控的目录中有一个文件被删除，就提交这个事件。Renamed——当被监控的目录中有一个文件被重命名，就提交这个事件。注：如果你没有将EnableRaisingEvents设为真，系统不会提交任何一个事件。如果有时FileSystemWatcher对象似乎无法工作，请首先检查EnableRaisingEvents，确保它被设为真。事件处理当FileSystemWatcher调用一个事件处理器时，它包含两个自变量——一个叫做“sender”的对象和一个叫做“e”的 FileSystemEventArgs对象。我们感兴趣的自变量为FileSystemEventArgs自变量。这个对象中包含有提交事件的原因。以下是FileSystemEventArgs对象的一些属性：属性：Name——这个属性中使事件被提交的文件的名称。其中并不包含文件的路径——只包含使用事件被提交的文件或目录名称。ChangeType——这是一个WatcherChangeTypes，它指出要提交哪个类型的事件。其有效值包括：ChangedCreatedDeletedRenamedFullPath——这个属性中包含使事件被提交的文件的完整路径，包括文件名和目录名。注意：FileSystemEventArgs对象是监控文件夹下有文件创建、删除、修改时的自变量，如果是重命名的话为RenamedEventArgs对象此时除了FileSystemEventArgs对象的属性值，多了一个OldFullPath，为重命名之前的文件名。大文件处理1. Create a new FileSystemWatcher.1System.IO.FileSystemWatcher fswXmlFileWatcher = new System.IO.FileSystemWatcher(); 2this.fswXmlFileWatcher.EnableRaisingEvents = true; 3this.fswXmlFileWatcher.Path =@“C:\Test“ 4//in here I only handle the file created event.5this.fswXmlFileWatcher.Created += newSystem.IO.FileSystemEventHandler(this.fswXmlFileWatcher_Created);2. Write Code to handle File Created Event.1private void fswXmlFileWatcher_Created(object sender, System.IO.FileSystemEventArgs e) 2{ 3lock(this) 4{ 5string filePath = e.FullPath; 6//incase the file is huge, it need some time to write the whole. so we wait untill the file is accessable by .Net7while (File.GetAttributes(filePath) == FileAttributes.Offline) 8{ 9Thread.Sleep(500); 10} 11//Ok. We start a new thread to process the file12ImportHelper ih = new ImportHelper(filePath); 13Thread th = new Thread(newThreadStart(ih.ImportXmlFile)); 14th.Start(); 15} 16}3. what is in the ImportHelper Class.1public class ImportHelper 2{ 3private string _filePath; 4private long _fileSize; 5private FileInfo _fileInfo; 6 7public ImportHelper(string filePath) 8{ 9this._filePath = filePath; 10this._fileSize = 0; 11this._fileInfo = newFileInfo(this._filePath); 12} 13 14//we need to this method. same reason. cause the file size is huge. 15private bool TestFile() 16{ 17long size = this._fileInfo.Length; 18if( this._fileSize == size ) 19{ 20return true; 21} 22else 23{ 24this._fileSize =size; 25return false; 26} 27} 28 29public void ImportXmlFile() 30{ 31while(!this.TestFile() ) 32{ 33Thread.Sleep(2000); 34} 35//It is ok now. The file is ready for us to process. 36//Write your own function to process the file.37ProcessMyFile(this._filePath) 38} 39}在一次文本文件变化的时候OnChanged事件会触发两次，这是因为除了文本内容变化之外还有文件其他的属性也变化了例如修改时间。为了解决这问题，也便于项目当中实际使用，写了下面几个类来实际使用：主方法：01 using System;02 using System.IO;0304 namespace test05 {06 class Program07 {08 static void Main(string args)09 {10111213 MyFileSystemWather myWather = new MyFileSystemWather(@“C:\test“, “*.txt“);14 myWather.OnChanged += new FileSystemEventHandler(OnChanged);15 myWather.OnCreated += new FileSystemEventHandler(OnCreated);16 myWather.OnRenamed += new RenamedEventHandler(OnRenamed);17 myWather.OnDeleted += new FileSystemEventHandler(OnDeleted);18 myWather.Start();19 //由于是控制台程序，加个输入避免主线程执行完毕，看不到监控效果20 Console.ReadKey();2122 }2324 private static void OnCreated(object source, FileSystemEventArgs e)25 {2627 Console.WriteLine(“文件新建事件处理逻辑“);2829 }3031 private static void OnChanged(object source, FileSystemEventArgs e)32 {3334 Console.WriteLine(“文件改变事件处理逻辑“);35 }3637 private static void OnDeleted(object source, FileSystemEventArgs e)38 {3940 Console.WriteLine(“文件删除事件处理逻辑“);41 }4243 private static void OnRenamed(object source, RenamedEventArgs e)44 {4546 Console.WriteLine(“文件重命名事件处理逻辑“);47 }4849 }50 }WatcherProcess类：01 using System.IO;0203 namespace test04 {05 public class WatcherProcess06 {07 private object sender;08 private object eParam;0910 public event RenamedEventHandler OnRenamed;11 public event FileSystemEventHandler OnChanged;12 public event FileSystemEventHandler OnCreated;13 public event FileSystemEventHandler OnDeleted;14 public event Completed OnCompleted;1516 public WatcherProcess(object sender, object eParam)17 {18 this.sender = sender;19 this.eParam = eParam;20 }2122 public void Process()23 {24 if (eParam.GetType() == typeof(RenamedEventArgs))25 {26 OnRenamed(sender, (RenamedEventArgs)eParam);27 OnCompleted(((RenamedEventArgs)eParam).FullPath);28 }29 else30 {31 FileSystemEventArgs e = (FileSystemEventArgs)eParam;32 if (e.ChangeType == WatcherChangeTypes.Created)33 {34 OnCreated(sender, e);35 OnCompleted(e.FullPath);36 }37 else if (e.ChangeType == WatcherChangeTypes.Changed)38 {39 OnChanged(sender, e);40 OnCompleted(e.FullPath);41 }42 else if (e.ChangeType == WatcherChangeTypes.Deleted)43 {44 OnDeleted(sender, e);45 OnCompleted(e.FullPath);46 }47 else48 {49 OnCompleted(e.FullPath);50 }51 }52 }53 }54 }MyFileSystemWather类：001 using System;002 using System.Collections;003 using System.IO;004 using System.Threading;005006 namespace test007 {008009 public delegate void Completed(string key);010011 public class MyFileSystemWather012 {013 private FileSystemWatcher fsWather;014015 private Hashtable hstbWather;016017 public event RenamedEventHandler OnRenamed;018 public event FileSystemEventHandler OnChanged;019 public event FileSystemEventHandler OnCreated;020 public event FileSystemEventHandler OnDeleted;021022 ///023 /// 构造函数024 ///025 /// 要监控的路径026 public MyFileSystemWather(string path, string filter)027 {028 if (!Directory.Exists(path))029 {030 throw new Exception(“找不到路径：“ + path);031 }032033 hstbWather = new Hashtable();034035 fsWather = new FileSystemWatcher(path);036 // 是否监控子目录037 fsWather.IncludeSubdirectories = false;038 fsWather.Filter = filter;039 fsWather.Renamed += new RenamedEventHandler(fsWather_Renamed);040 fsWather.Changed += new FileSystemEventHandler(fsWather_Changed);041 fsWather.Created += new FileSystemEventHandler(fsWather_Created);042 fsWather.Deleted += new FileSystemEventHandler(fsWather_Deleted);043 }044045 ///046 /// 开始监控047 ///048 public void Start()049 {050 fsWather.EnableRaisingEvents = true;051 }052053 ///054 /// 停止监控055 ///056 public void Stop()057 {058 fsWather.EnableRaisingEvents = false;059 }060061 ///062 /// filesystemWatcher 本身的事件通知处理过程063 ///064 ///065 ///066 private void fsWather_Renamed(object sender, RenamedEventArgs e)067 {068 lock (hstbWather)069 {070 hstbWather.Add(e.FullPath, e);071 }072073 WatcherProcess watcherProcess = new WatcherProcess(sender, e);074 watcherProcess.OnCompleted += new Completed(WatcherProcess_OnCompleted);075 watcherProcess.OnRenamed += new RenamedEventHandler(WatcherProcess_OnRenamed);076 Thread thread = new Thread(watcherProcess.Process);077 thread.Start();078 }079080 private void WatcherProcess_OnRenamed(object sender, RenamedEventArgs e)081 {082 OnRenamed(sender, e);083 }084085 private void fsWather_Created(object sender, FileSystemEventArgs e)086 {087 lock (hstbWather)088 {089 hstbWather.Add(e.FullPath, e);090 }091 WatcherProcess watcherProcess = new WatcherProcess(sender, e);092 watcherProcess.OnCompleted += new Completed(WatcherProcess_OnCompleted);093 watcherProcess.OnCreated += new FileSystemEventHandler(WatcherProcess_OnCreated);094 Thread threadDeal = new Thread(watcherProcess.Process);095 threadDeal.Start();096 }097098 private void WatcherProcess_OnCreated(object sender, FileSystemEventArgs e)099 {100 OnCreated(sender, e);101 }102103 private void fsWather_Deleted(object sender, FileSystemEventArgs e)104 {105 lock (hstbWather)106 {107 hstbWather.Add(e.FullPath, e);108 }109 WatcherProcess watcherProcess = new WatcherProcess(sender, e);110 watcherProcess.OnCompleted += new Completed(WatcherProcess_OnCompleted);111 watcherProcess.OnDeleted += new FileSystemEventHandler(WatcherProcess_OnDeleted);112 Thread tdDeal = new Thread(watcherProcess.Process);113 tdDeal.Start();114 }115116 private void WatcherProcess_OnDeleted(object sender, FileSystemEventArgs e)117 {118 OnDeleted(sender, e);119 }120121 private void fsWather_Changed(object sender, FileSystemEventArgs e)122 {123 if (e.ChangeType == WatcherChangeTypes.Changed)124 {125 if (hstbWather.ContainsKey(e.FullPath))126 {127 WatcherChangeTypes oldType = ((FileSystemEventArgs)hstbWather[e.FullPath]).ChangeType;128 if (oldType == WatcherChangeTypes.Created || oldType == WatcherChangeTypes.Changed)129 {130 return;131 }132 }133 }134135 lock (hstbWather)136 {137 hstbWather.Add(e.FullPath, e);138 }139 WatcherProcess watcherProcess = new WatcherProcess(sender, e);140 watcherProcess.OnCompleted += new Completed(WatcherProcess_OnCompleted);141 watcherProcess.OnChanged += new FileSystemEventHandler(WatcherProcess_OnChanged);142 Thread thread = new Thread(watcherProcess.Process);143 thread.Start();144 }145146 private void WatcherProcess_OnChanged(object sender, FileSystemEventArgs e)147 {148 OnChanged(sender, e);149 }150151 public void WatcherProcess_OnCompleted(string key)152 {153 lock (hstbWather)154 {155 hstbWather.Remove(key);156 }157 }158 }159 }使用了线程安全的Hashtable来处理一次改变触发两次事件的问题，要注意的是在实际项目使用中，在通过监控文件事情触发时开一个线程WatcherProcess去处理自己业务逻辑的时候，不管业务逻辑成功或者失败（例如有异常抛出一定要try一下）一定要让WatcherProcess的 Completed也就是MyFileSystemWather的WatcherProcess_OnCompleted执行去移除对应变化文件的Hashtable的key，不然下次此文件改变时是无法触发你的业务逻辑的。还有就是在进行文件监控的时候， 被监控文件在写入的时候，是会有I/O冲突的，即使写入文件是FileShare.Read的也会出现，要真正解决貌似只有FileMaping方法，但是我的项目中文本的写入软件不是我们能控制的，所以只有用处理异常的方法来解决。
FileSystemWatcher怎么动态创建和监测多个文件夹
如果那些文件夹比较分散，只有一对一监控了：创建文件夹后，创建相应的FileSystemWatcher如果都在某个根目录里，那就只监视根目录好了，处理Created事件var fileWatcher = new FileSystemWatcher(path);//fileWatcher.NotifyFilter这里这个可不用设置fileWatcher.Created += new FileSystemEventHandler(OnCreated);fileWatcher.Changed += new FileSystemEventHandler(OnChanged);fileWatcher.EnableRaisingEvents = true; //启用监控
filesystemwatcher组件事件不触发
我也遇到很多问题,有时候真实奇怪了，我的电脑不能单独触发NotifyFilters.LastWrite，但是远程操作其他人的可以。我的加上个重复的，他处理两次也不会出现错误，别人的就是不行，我知道他就是个异步控件，方法我也写了跨线程使用方法，后来我明白了，对于这种东西本身就存在问题，在他上面下功夫是徒劳，干脆像我，看这招毒不毒我就这样写：
void watch_file() { FileSystemWatcher fsw = new FileSystemWatcher(); fsw.Path = logen.downpath; fsw.Filter = “*.gpg“; fsw.EnableRaisingEvents = true; fsw.IncludeSubdirectories = true; fsw.NotifyFilter = NotifyFilters.Attributes| NotifyFilters.LastWrite; fsw.Changed+= (object ob, FileSystemEventArgs wd) =》 { fsw.EnableRaisingEvents = false; Thread.Sleep(500); runfilelisen(); fsw.Dispose(); watch_file(); }; }
c# filesystemwatcher 监控文件是否写完
类型里面有个NotifyFilters.LastWrite好像什么滴，然后要用他的changed事件，千万别用created事件。很多人在网上复制一大堆的：NotifyFilters.LastAccess | NotifyFilters.LastWrite| NotifyFilters.FileName | NotifyFilters.DirectoryName;奇了怪了，怎么处理了两次？？？？你自己写的代码要自己去看，网上那么多人说是filesystemwatcher问题，看看到底是哪里问题，对于文件名的changed确实是改变了三次啊，改变了FileName的时候，肯定也改变了LastAccess，有人还发现处理了三次呢，为什么？？？他监控下载文件夹，下载文件是创建了，然后改名创建，LastWrite也包括了，触发changed三次！DirectoryName这个东西是没用的，只能触发一次，后面就拜拜，因为你的代码检测他啊，他改变一次，filesystemwatcher在原来的路径就找不到他了，又要重新发现文件，这时候的文件名你已经改了。所以我上面说那么多，就会引来后面的问题，系统会溢出奔溃，其实这个控件是个异步控件，正在里面使用控件要委托，避免跨线程检查；方法使用try,catch机制会跳转，没有cacth到，就跳了；一连执行三次一样的方法去操作文件，有可能第一次把文件删除了，第二次交叉执行又去使用文件路径，你说找不到路径的System.IO类型操作是不是系统溢出，这样就会奔溃。这个控件还有一个小问题，你要注意framework版本，是否认识NotifyFilters.LastWrite
C# FileSystemWatcher组件
使用 FileSystemWatcher 组件可以监视文件系统，并在文件系统所包含的目录和文件发生更改时作出响应。这使您可以在特定的文件和目录被创建、修改或删除时，快速方便地启动业务处理。例如，假设您和一群同事正合作处理某个文档，而该文档存储在服务器上的共享目录下。使用 FileSystemWatcher 组件的实例，您可以编写自己的应用程序来监视共享目录内容的更改。当检测到更改时，该组件就可以运行过程，通过电子邮件通知小组的每一个成员。下面的示例创建 FileSystemWatcher 来监视运行时指定的目录。组件设置为监视 LastWrite 和 LastAccess 时间方面的更改，以及目录中文本文件的创建、删除或重命名。如果更改、创建或删除文件，文件路径将被输出到控制台。在文件重命名后，旧路径和新路径都输出到控制台。在此示例中使用 System.Diagnostics 和 System.IO 命名空间。public class Watcher{ public static void Main() { Run(); } [PermissionSet(SecurityAction.Demand, Name=“FullTrust“)] public static void Run() { string args = System.Environment.GetCommandLineArgs(); // If a directory is not specified, exit program. if(args.Length != 2) { // Display the proper way to call the program. Console.WriteLine(“Usage: Watcher.exe (directory)“); return; } // Create a new FileSystemWatcher and set its properties. FileSystemWatcher watcher = new FileSystemWatcher(); watcher.Path = args; /* Watch for changes in LastAccess and LastWrite times, and the renaming of files or directories. */ watcher.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.DirectoryName; // Only watch text files. watcher.Filter = “*.txt“; // Add event handlers. watcher.Changed += new FileSystemEventHandler(OnChanged); watcher.Created += new FileSystemEventHandler(OnChanged); watcher.Deleted += new FileSystemEventHandler(OnChanged); watcher.Renamed += new RenamedEventHandler(OnRenamed); // Begin watching. watcher.EnableRaisingEvents = true; // Wait for the user to quit the program. Console.WriteLine(“Press \’q\’ to quit the sample.“); while(Console.Read()!=’q’); } // Define the event handlers. private static void OnChanged(object source, FileSystemEventArgs e) { // Specify what is done when a file is changed, created, or deleted. Console.WriteLine(“File: “ + e.FullPath + “ “ + e.ChangeType); } private static void OnRenamed(object source, RenamedEventArgs e) { // Specify what is done when a file is renamed. Console.WriteLine(“File: {0} renamed to {1}“, e.OldFullPath, e.FullPath); }}建议看下MSDN
c# 中的FileSystemWatcher问题
有两种办法可以解决1、可以设置文件监视的类型 FileSystemWatcher fileWatcher = new FileSystemWatcher(); fileWatcher.NotifyFilter2、可以通过FileSystemEventArgs类的ChangeType属性去判断，是否为创建文件引发的事件 void fileWatcher_Changed(object sender, FileSystemEventArgs e){ if (e.ChangeType == WatcherChangeTypes.Created) { }}
C#用filesystemwatcher监控文件夹变化时，怎样监控到被监控的文件夹本身变化
一般的做法就是监视上一层目录。Path设置成上一级目录，Filter设置成文件夹名称。http://social.msdn.microsoft.com/Forums/vstudio/en-US/a17f54f2-65eb-4add-afa9-aacf95ca80e5/filesystemwatcher-how-to-get-an-event-trigger-for-watcher-folder
c#FileSystemWatcher如何监视【远程计算机】文件，非本地计算机，谢谢！
最简单的和最快的方法是建立ftp，上传到本机。ftp有一种绿色的小工具，在远程计算机上启动指向你要下载的目录，你在本机输入那台机的ip地址就可以访问远程电脑的目录。