FileSystemWatcherEx

A simple enhanced class based on .net official FileSystemWatcher.

This class attempts to do something better

• Try fire same event only one time, FileSystemWatcher may fire multiple times.
• check whether file is ready for read write. FileSystemWatcher fire event immediately.
• enhanced filter, support monitoring multiple extensions. As far as I know, FileSystemWatcher does not support.

Limitation

DO NOT keep the file open in your callback, open it and close it as soon as possible. then you should be safe.

I demonstrate a bad callback implementation in demo project. run it with -p option to see it.

Example usage

public void OnFileChanged(object sender, System.IO.FileSystemEventArgs e)
{
  if (e.ChangeType == System.IO.WatcherChangeTypes.Created 
     || e.ChangeType == System.IO.WatcherChangeTypes.Changed)
  {
    // do something.
  }
}

// monitor .bmp and .jpg and .png files and .docx files begin with a
var filters = "*.bmp|*.jpg|*.png|a*.docx";

var monitorPath = System.AppDomain.CurrentDomain.BaseDirectory;
var fileWatcherEx = new FileSystemWatcherEx(monitorPath
    , filters
    , true
    , ""
    , OnFileChanged
    , OnFileChanged
    , OnFileChanged
);

fileWatcherEx.Start();

// when finish monitoring

fileWatcherEx.Stop();

Demo Project

this demo project will monitor program directory recursively, and display changed .bmp file.