How can you watch for file changes like creation or deletion in real-time?

Question

ICSM Computer · Answer

To watch for file changes (like creation, deletion, or modification) in real-time in C#, you can use the built-in
FileSystemWatcher class in the System.IO namespace.
Example: Monitor a directory for changes
using System;
using System.IO;
class Program
{
    static void Main()
    {
        string pathToWatch = @"C:\MyFolder";
        using (FileSystemWatcher watcher = new FileSystemWatcher(pathToWatch))
        {
            // Watch for changes in LastWrite times, and creation/deletion of files
            watcher.NotifyFilter = NotifyFilters.FileName | NotifyFilters.LastWrite | NotifyFilters.CreationTime;
            // Only watch text files
            watcher.Filter = "*.txt";
            // Event handlers
            watcher.Created += OnCreated;
            watcher.Deleted += OnDeleted;
            watcher.Changed += OnChanged;
            watcher.Renamed += OnRenamed;
            // Begin watching
            watcher.EnableRaisingEvents = true;
            Console.WriteLine("Watching for changes. Press Enter to exit...");
            Console.ReadLine();  // Keep the program running
        }
    }
    private static void OnCreated(object sender, FileSystemEventArgs e) =andgt;
        Console.WriteLine($"File created: {e.FullPath}");
    private static void OnDeleted(object sender, FileSystemEventArgs e) =andgt;
        Console.WriteLine($"File deleted: {e.FullPath}");
    private static void OnChanged(object sender, FileSystemEventArgs e) =andgt;
        Console.WriteLine($"File changed: {e.FullPath}");
    private static void OnRenamed(object sender, RenamedEventArgs e) =andgt;
        Console.WriteLine($"File renamed: {e.OldFullPath} -andgt; {e.FullPath}");
}
Notes:
FileSystemWatcher supports events: Created, Deleted,
Changed, and Renamed.Use IncludeSubdirectories = true to monitor subfolders.It's best suited for local directories (not reliable over network shares).

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How can you watch for file changes like creation or deletion in real-time?

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Example: Monitor a directory for changes

Notes:

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