Regex reg = new Regex(@\"^[0-9]*\\.wav\"); Stack wavefiles= new Stack(Directory.GetFiles(\"c:\\\\WaveFiles\", \"*.wav\").Where(path =&
Regex reg = new Regex(@"^[0-9].wav"); wavefiles = new Stack(Directory.GetFiles(FolderName, ".wav").Where(path => reg.IsMatch(Path.GetFileName(path))));