iSpyApplication.Controls.VolumeLevel.ScanFiles C# (CSharp) Method

        private void ScanFiles()
        {
            try
            {
                //check files exist
                var dirinfo = new DirectoryInfo(Dir.Entry + "audio\\" + Micobject.directory + "\\");

                var lFi = new List<FileInfo>();
                lFi.AddRange(dirinfo.GetFiles());
                lFi = lFi.FindAll(f => f.Extension.ToLower() == ".mp3" || f.Extension.ToLower() == ".mp4");
                lFi = lFi.OrderByDescending(f => f.CreationTime).ToList();

                //var farr = _filelist.ToArray();
                lock (_lockobject)
                {
                    for (int j = 0; j < _filelist.Count; j++)
                    {
                        var t = _filelist[j];
                        if (t != null)
                        {
                            var fe = lFi.FirstOrDefault(p => p.Name == t.Filename);
                            if (fe == null)
                            {
                                //file not found
                                _filelist.RemoveAt(j);
                                j--;
                                continue;
                            }
                            lFi.Remove(fe);
                        }
                    }
                    //add missing files
                    foreach (var fi in lFi)
                    {
                        _filelist.Add(new FilesFile
                                            {
                                                CreatedDateTicks = fi.CreationTime.Ticks,
                                                Filename = fi.Name,
                                                SizeBytes = fi.Length,
                                                MaxAlarm = 0,
                                                AlertData = "0",
                                                DurationSeconds = 0,
                                                IsTimelapse = false,
                                                IsMergeFile = fi.Name.ToLower().IndexOf("merge", StringComparison.Ordinal) !=-1
                                            });
                    }
                }
            }
            catch (Exception ex)
            {
                ErrorHandler?.Invoke(ex.Message);
            }
            FileListUpdated?.Invoke(this);
        }