How do you log all file system operations (create, read, write, delete) in an application?

Question

ICSM Computer · Answer

To log all file system operations (create, read, write, delete) in a C# application, you need to manually intercept or wrap each file operation since .NET
does not automatically log them.
Here are common strategies:
1. Wrap File Access in a Logging Utility Class
Create a custom static helper class that logs every file operation.
using System;
using System.IO;
public static class FileLogger
{
    public static string ReadAllText(string path)
    {
        Log("READ", path);
        return File.ReadAllText(path);
    }
    public static void WriteAllText(string path, string content)
    {
        Log("WRITE", path);
        File.WriteAllText(path, content);
    }
    public static void Delete(string path)
    {
        Log("DELETE", path);
        File.Delete(path);
    }
    public static void Create(string path)
    {
        Log("CREATE", path);
        using (File.Create(path)) { }
    }
    private static void Log(string action, string path)
    {
        Console.WriteLine($"{DateTime.Now}: {action} -andgt; {path}");
        // Or write to a log file or database
    }
}
2. Use FileSystemWatcher for External Monitoring
Use FileSystemWatcher to detect file changes in real time within a directory.
using System;
using System.IO;
class Watcher
{
    public static void StartWatching(string folderPath)
    {
        var watcher = new FileSystemWatcher(folderPath)
        {
            IncludeSubdirectories = true,
            EnableRaisingEvents = true
        };
        watcher.Created += (s, e) =andgt; Console.WriteLine($"Created: {e.FullPath}");
        watcher.Changed += (s, e) =andgt; Console.WriteLine($"Changed: {e.FullPath}");
        watcher.Deleted += (s, e) =andgt; Console.WriteLine($"Deleted: {e.FullPath}");
        watcher.Renamed += (s, e) =andgt; Console.WriteLine($"Renamed: {e.OldFullPath} → {e.FullPath}");
    }
}
Note: FileSystemWatcher does not detect read operations and can sometimes miss events under high activity.
3. Optional: Use Interception or AOP
For larger applications:Use Aspect-Oriented Programming (AOP) (e.g., PostSharp) to intercept methods.For advanced scenarios, hook into Windows API using tools like
ETW (Event Tracing for Windows) or Detours (native-level, not C#).
Summary
Method
Captures Read
Write
Delete
Remarks
Logging Wrapper (C#)
Yes
Yes
Yes
Best control; manual
FileSystemWatcher
No
Yes
Yes
External, async
Windows Audit Policy
Yes
Yes
Yes
System-wide; needs admin
Read More
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How do you log all file system operations (create, read, write, delete) in an application?

ICSM Computer

Can you answer this question?

1 Answers

1. Wrap File Access in a Logging Utility Class

2. Use `FileSystemWatcher` for External Monitoring

3. Optional: Use Interception or AOP

Summary

Liked By

Method	Captures Read	Write	Delete	Remarks
Logging Wrapper (C#)	Yes	Yes	Yes	Best control; manual
`FileSystemWatcher`	No	Yes	Yes	External, async
Windows Audit Policy	Yes	Yes	Yes	System-wide; needs admin