ช่วยด้วยครับ ต้องการทำโค๊ดให้เป็น Thread ต้องเขียนยังไงครับ

public static System.Collections.Generic.List<string> GetFilesRecursive(string initial)
        {
            System.Collections.Generic.List<string> result = new System.Collections.Generic.List<string>();
            System.Collections.Generic.Stack<string> stack = new System.Collections.Generic.Stack<string>();
            stack.Push(initial);
            while ((stack.Count > 0))
            {
                string dir = stack.Pop();
                result.AddRange(System.IO.Directory.GetFiles(dir, "*.lyr")); //ตรงนี้อยากแยกไฟล์ออกมาเพื่อโยนไป  private void _ArtisSong(string pathFileName)
                string directoryName = null;
                foreach (string directoryName_loopVariable in System.IO.Directory.GetDirectories(dir))
                {
                    directoryName = directoryName_loopVariable;
                    stack.Push(directoryName);
                }
            }
            return result;
        }

 private void _ArtisSong(string pathFileName)
        {
            Random rnd = new Random();
            string result = "" + rnd.Next(1, 99999) + rnd.Next(1, 99999) + rnd.Next(1, 99999) + rnd.Next(1, 99999) + rnd.Next(1, 99999) + rnd.Next(1, 99999) + rnd.Next(1, 99999) + rnd.Next(1, 99999);

            try
            {
                result = (string)System.IO.File.ReadLines(pathFileName, System.Text.Encoding.GetEncoding(874)).Skip(1).Take(1).First() + " ; " + (string)System.IO.File.ReadLines(pathFileName, System.Text.Encoding.GetEncoding(874)).Skip(0).Take(1).First(); ;

            }
            catch { }

            songTableAdapter.Insert(pathFileName, result.Replace("(G)", "").Replace("( C )", "").
                            Replace("( Cm )", "").Replace("( C# )", "").Replace("( C#m )", "").
                            Replace("( D )", "").Replace("( Dm )", "").Replace("( E )", "").
                            Replace("( Eb )", "").Replace("( Ebm )", "").Replace("( Em )", "").
                            Replace("( F )", "").Replace("( Fm )", "").Replace("( F# )", "").
                            Replace("( F#m )", "").Replace("( G )", "").Replace("( Gb )", "").
                            Replace("( Gm )", "").Replace("( A )", "").Replace("( Ab )", "").
                            Replace("( Am )", "").Replace("( Abm )", "").Replace("( B )", "").
                            Replace("( Bb )", "").Replace("( Bm )", "").Replace("( Bbm )", "").Trim());
        }