Get Username of an Accesed File

I would like to get the username of an accessed file (add, delete, rename,...). actually I use filesystemwatcher to monitor the file access and I have activated object access on an directory to get userinformation via eventlogs. This solution is not perfect, because there are a lot of file events and the eventlog messages are not so detailed. there is just one eventd id for write data. this it is used for add file, rename , move,... every write data. Additionally I had to crosscheck that the eventlog message matches the filesystemwatcher event. I would prefer handle this better. so i spend al lot of time googleing, reading, ... I know there is another post on stackoverflow

Get username of opened file

but i think there should be a possible solution because Windows Events can get the username.

with reading on a few pages i disovered that there should be a possible solution using netapi32.dll. the example code on http://vbcity.com/forums/t/133307.aspx?PageIndex=2 doesn't work for me. i was unable to get the fileid so i changed the code to

private ulong GetFileIdFromPath(string filePath)
{

  WinAPI.BY_HANDLE_FILE_INFORMATION objectFileInfo = new WinAPI.BY_HANDLE_FILE_INFORMATION();

  Thread.Sleep(200);

  FileInfo fi = new FileInfo(filePath);

  FileStream fs = fi.Open(FileMode.Open, FileAccess.Read, FileShare.Read);

  WinAPI.GetFileInformationByHandle(fs.Handle, out objectFileInfo);


  fs.Close();


 ulong fileIndex = ((ulong)objectFileInfo.FileIndexHigh << 32) + (ulong)objectFileInfo.FileIndexLow;

  return fileIndex; 

}

with this code I'm able to get the fileid but with the fileid and the example code I'm unable to get the username.

From My last program ( 2 week ago) - I was asked to audit change in files ( also the user name)

the Solution was by filesystemwatcher and after an event -> goto the Event Log of windows and bu Xpath search - To find which user made the action.

   public static EventUnit DisplayEventAndLogInformation(string fileToSearch, DateTime actionTime)
        {
            StringBuilder sb = new StringBuilder();
            const string queryString = @"<QueryList>
  <Query Id=""0"" Path=""Security"">
    <Select Path=""Security"">*</Select>
  </Query>
</QueryList>";
            EventLogQuery eventsQuery = new EventLogQuery("Security", PathType.LogName, queryString);
            eventsQuery.ReverseDirection = true;
            EventLogReader logReader = new EventLogReader(eventsQuery);
            EventUnit e = new EventUnit();
            bool isStop = false;
            for (EventRecord eventInstance = logReader.ReadEvent(); null != eventInstance; eventInstance = logReader.ReadEvent())
            {
                foreach (var VARIABLE in eventInstance.Properties)
                    if (VARIABLE.Value.ToString().ToLower().Contains(fileToSearch.ToLower()) && actionTime.ToString("d/M/yyyy HH:mm:ss") == eventInstance.TimeCreated.Value.ToString("d/M/yyyy HH:mm:ss"))
                    {
                        foreach (var VARIABLE2 in eventInstance.Properties) sb.AppendLine(VARIABLE2.Value.ToString());
                        e.Message = sb.ToString();
                        e.User = (eventInstance.Properties.Count > 1) ? eventInstance.Properties[1].Value.ToString() : "n/a";
                        e.File = fileToSearch;
                        isStop = true;
                        break;
                    }
                if (isStop) break;
                try
                {
                    //    Console.WriteLine("Description: {0}", eventInstance.FormatDescription());
                }
                catch (Exception e2)
                {
                }
            }
            return e;
        }