DirectoryInfo

            //DirectoryInfo di = new DirectoryInfo(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments));
            //Directory.CreateDirectory(di + @"\PGPowerPoint\");
            //Directory.CreateDirectory(di + @"\PGPowerPoint\" + @"\StudentLists\");
            //listsDirectory = new DirectoryInfo(di + @"\PGPowerPoint\" + @"\StudentLists\");