public void CreateTestData()
 {
     data = new List<Song>();
     Song s = new Song();
     s.Title = "Halo";
     s.Artist = "Beyonce";
     s.Album = "I Am... Sasha Fierce Deluxe Edition";
     s.Length = "04:21";
     s.MusicType = "西洋歌曲";
     s.Offline = true;
     s.HasLyrics = true;
     s.Favorite = true;
     data.Add(s);
     Song ss;
     for(int i= 0 ;i<30000;i++)
     {
         ss = new Song();
         ss.Title = "累";
         ss.Artist = "韋禮安";
         ss.Album = "有人在等";
         ss.Length = "04:33";
         ss.MusicType = "國語歌曲";
         data.Add(ss);
     }
 }
        public void CreateTestDataFromDb()
        {
            SongList = new List<Song>();
            using (DbConnection conn = new SQLiteConnection("Data source=song.db3"))
            {
                conn.ConnectionString = "Data Source=song.db3";
                conn.Open();
                DbCommand cmd = conn.CreateCommand();
                try
                {
                    cmd.CommandText = "SELECT * FROM song";
                    DbDataReader sqlite_datareader = cmd.ExecuteReader();
                    while (sqlite_datareader.Read())
                    {
                        Song s = new Song();
                        s.Title = sqlite_datareader["Title"].ToString();
                        s.Artist = sqlite_datareader["Artist"].ToString();
                        s.Album = sqlite_datareader["Album"].ToString();
                        s.Length = sqlite_datareader["Length"].ToString();
                        s.MusicType = sqlite_datareader["MusicType"].ToString();
                        s.Offline = Boolean.Parse( sqlite_datareader["Offline"].ToString());
                        s.HasLyrics = Boolean.Parse(sqlite_datareader["HasLyrics"].ToString());
                        s.Favorite = Boolean.Parse(sqlite_datareader["Favorite"].ToString());
                        SongList.Add(s);
                    }

                }
                catch
                {
                    throw;
                }
            }
        }
        public void CopyDataToMemory()
        {
            SongList = new List<Song>();

            for (int i = 0; i < data.Count; i++)
            {
                Song s = new Song();
                s.Title = data[i].Title;
                s.Artist = data[i].Artist;
                s.Album = data[i].Album;
                s.Length = data[i].Length;
                s.MusicType = data[i].MusicType;
                s.Offline = data[i].Offline;
                s.HasLyrics = data[i].HasLyrics;
                s.Favorite = data[i].Favorite;
                SongList.Add(s);
            }
        }