How can I monitor a Windows directory for changes?

Question

When a change is made within a directory on a Windows system, I need a program to be notified immediately of the change.

Is there some way of executing a program whe

Answer 1

I came on this page while searching for a way to monitor filesystem activity. I took Refracted Paladin's post and the FileSystemWatcher that he shared and wrote a quick-and-dirty working C# implementation:

using System;
using System.IO;

namespace Folderwatch
{
    class Program
    {
        static void Main(string[] args)
        {

            //Based on http://stackoverflow.com/questions/760904/how-can-i-monitor-a-windows-directory-for-changes/27512511#27512511
            //and http://msdn.microsoft.com/en-us/library/system.io.filesystemwatcher.aspx

            string pathToFolder = string.Empty;
            string filterPath = string.Empty;
            const string USAGE = "USAGE: Folderwatch.exe PATH FILTER \n\n e.g.:\n\n Folderwatch.exe c:\\windows *.dll";

            try
            {
                pathToFolder = args[0];

            }
            catch (Exception)
            {
                Console.WriteLine("Invalid path!");
                Console.WriteLine(USAGE);
                return;
            }

            try
            {
                filterPath = args[1];
            }
            catch (Exception)
            {
                Console.WriteLine("Invalid filter!");
                Console.WriteLine(USAGE);
                return;

            }

            FileSystemWatcher watcher = new FileSystemWatcher();

            watcher.Path = pathToFolder;
            watcher.Filter = filterPath;

            watcher.NotifyFilter = NotifyFilters.Attributes | NotifyFilters.CreationTime | 
                NotifyFilters.DirectoryName | NotifyFilters.FileName | NotifyFilters.LastAccess | 
                NotifyFilters.LastWrite | NotifyFilters.Security | NotifyFilters.Size;

            // 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("Monitoring File System Activity on {0}.", pathToFolder);
            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);
        }
    }
}

To use this, download Visual Studio (Express will do). The create a new C# console application called Folderwatch and copy and paste my code into your Program.cs.

As an alternative you could use Sys Internals Process Monitor: Process Monitor It can monitor the file system and a bunch more.