C# FileSystemWatcher监听文件事件

现有一个需求如下：监控某个目录中的文件修改，创建，删除等信息，并记录下来.

这里用到FileSystemWatcher类.由于考虑到文件的写入量会很频率，所以考虑先将监听到的消息记录到内存中。

监听部分的代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace FileEventListener
{
public partial class FSWControl : Form
{
static int count = 0;
static FileSystemWatcher watcher = new FileSystemWatcher();
static int eventCount = 0;

//static List<string> files = new List<string>();
public FSWControl()
{
InitializeComponent();
WatcherStrat(@"D:\test\", "*.tr", true, true);
}

/// <summary>
/// 初始化监听
/// </summary>
/// <param name="StrWarcherPath">需要监听的目录</param>
/// <param name="FilterType">需要监听的文件类型(筛选器字符串)</param>
/// <param name="IsEnableRaising">是否启用监听</param>
/// <param name="IsInclude">是否监听子目录</param>
private static void WatcherStrat(string StrWarcherPath, string FilterType, bool IsEnableRaising, bool IsInclude)
{
//初始化监听
watcher.BeginInit();
//设置监听文件类型
watcher.Filter = FilterType;
//设置是否监听子目录
watcher.IncludeSubdirectories = IsInclude;
//设置是否启用监听?
watcher.EnableRaisingEvents = IsEnableRaising;
//设置需要监听的更改类型(如:文件或者文件夹的属性,文件或者文件夹的创建时间;NotifyFilters枚举的内容)
watcher.NotifyFilter = NotifyFilters.Attributes | NotifyFilters.CreationTime | NotifyFilters.DirectoryName | NotifyFilters.FileName | NotifyFilters.LastAccess | NotifyFilters.LastWrite | NotifyFilters.Security | NotifyFilters.Size;
//设置监听的路径
watcher.Path = StrWarcherPath;
//注册创建文件或目录时的监听事件
//watcher.Created += new FileSystemEventHandler(watch_created);
//注册当指定目录的文件或者目录发生改变的时候的监听事件
watcher.Changed += new FileSystemEventHandler(watch_changed);
//注册当删除目录的文件或者目录的时候的监听事件
watcher.Deleted += new FileSystemEventHandler(watch_deleted);
//当指定目录的文件或者目录发生重命名的时候的监听事件
watcher.Renamed += new RenamedEventHandler(watch_renamed);
//结束初始化
watcher.EndInit();
}

/// <summary>
/// 创建文件或者目录时的监听事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private static void watch_created(object sender, FileSystemEventArgs e)
{
//事件内容
output("create:" + e.FullPath);
}

/// <summary>
/// 当指定目录的文件或者目录发生改变的时候的监听事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private static void watch_changed(object sender, FileSystemEventArgs e)
{
//事件内容
//事件内容
output("change:" + e.FullPath);
}
/// <summary>
/// 当删除目录的文件或者目录的时候的监听事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private static void watch_deleted(object sender, FileSystemEventArgs e)
{
//事件内容
output("del:" + e.FullPath);
}
/// <summary>
/// 当指定目录的文件或者目录发生重命名的时候的事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private static void watch_renamed(object sender, RenamedEventArgs e)
{
//事件内容
output("rename:" + e.FullPath);
}
/// <summary>
/// 启动或者停止监听
/// </summary>
/// <param name="IsEnableRaising">True:启用监听,False:关闭监听</param>
private void WatchStartOrSopt(bool IsEnableRaising)
{
watcher.EnableRaisingEvents = IsEnableRaising;
}

private static void output(string text)
{
//FileStream fs = new FileStream("D:\\listen.txt", FileMode.Append);
//StreamWriter sw = new StreamWriter(fs, Encoding.Default);
//sw.WriteLine(text);
//sw.Close();
//fs.Close();
//files.Add(text);
eventCount++;

}

private void button1_Click(object sender, EventArgs e)
{
string name = count.ToString() + "_" + eventCount.ToString();
FileStream fs = new FileStream("D:\\listen_" + name + ".txt", FileMode.Append);
StreamWriter sw = new StreamWriter(fs, Encoding.Default);
//foreach (string text in files)
//{
//    sw.WriteLine(text);
//}
sw.WriteLine("共收到事件:" + eventCount.ToString());
//files.Clear();
eventCount = 0;
sw.Close();
fs.Close();
count++;
MessageBox.Show("打印完成:" + name, "提示", MessageBoxButtons.OK);
}

private void button2_Click(object sender, EventArgs e)
{
WatchStartOrSopt(false);
}

private void button3_Click(object sender, EventArgs e)
{
WatchStartOrSopt(true);
}
}
}

然后写一个生成文件的程序用于测试，由于可能需要多个写入一起跑，采用传入参数的方式进行调用程序。共三个参数：第一个为标识，第二个为生成文件的数量，第三个为开始运行的时间:

如 FileCreater.exe 1 1000 121000 则表示这个实例的名称为1，连续生成1000个文件，在12：10：00开始执行。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace FileCreater
{
public partial class Form1 : Form
{
string filePre = "";
string startTime = "";

public Form1(string[] args)
{
filePre = args[0];
startTime = args[2];
InitializeComponent();

timer1.Interval = 100;
timer1.Tick += button1_Click;
timer1.Enabled = true;
this.Text = "FileCreater" + filePre + "_" + startTime;
this.numericUpDown1.Value = int.Parse(args[1]);
}

private void button1_Click(object sender, EventArgs e)
{
label3.Text = DateTime.Now.ToString("HHmmss") + "|" + startTime;
if (int.Parse(DateTime.Now.ToString("HHmmss")) > int.Parse(startTime))
{
label3.Text = numericUpDown1.Value.ToString();
for (int i = 1; i <= numericUpDown1.Value; i++)
{
//string time = DateTime.Now.ToString("ddhhMMss");
string file = string.Format(@"{0}\{1}_{2}.tr", textBox1.Text, i, filePre);
FileStream fs = new FileStream(file, FileMode.Append);
StreamWriter sw = new StreamWriter(fs, Encoding.Default);
sw.WriteLine(i.ToString());
sw.Close();
fs.Close();
}
timer1.Stop();
}
//MessageBox.Show("已完成", "提示", MessageBoxButtons.OK);

Application.Exit();
}
}
}

测试过程中发现如下现象：

1.一个生成文件程序，连续生成10W的文件时会发生计数器记录下的值小于或多于10W