Cannot deserialize the current JSON object xamarin.forms - xamarin

Question

Im using xamarin.forms to create an app that uses the MusixMatch api. It's throwing the following exception : Cannot deserialize the current JSON object (e.g. {\"name\":\"value\"}) into type 'System.Collections.Generic.List. To my knowledge, Ive done everything correctly, not sure why this exception is being thrown. Any help will be appreciated.
TrackList.cs
public class TrackList
{
public class Track
{
public int track_id { get; set; }
public string track_mbid { get; set; }
public string track_isrc { get; set; }
public string track_spotify_id { get; set; }
public string track_soundcloud_id { get; set; }
public string track_xboxmusic_id { get; set; }
public string track_name { get; set; }
public int track_rating { get; set; }
public int track_length { get; set; }
public int commontrack_id { get; set; }
public int instrumental { get; set; }
}
public class Body
{
public IList<Track> track_list { get; set; }
}
}
Api Request
public async void SearchBtn(object sender, EventArgs e)
{
List<TrackList.Track> trans = new List<TrackList.Track>();
string search = SearchField.Text;
try
{
var content = "";
HttpClient client = new HttpClient();
var RestUrl = "http://api.musixmatch.com/ws/1.1/track.search?q_track=" + search + "&page_size=3&page=1&s_track_rating=desc";
client.BaseAddress = new Uri(RestUrl);
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.GetAsync(RestUrl);
content = await response.Content.ReadAsStringAsync();
var items = JsonConvert.DeserializeObject<List<TrackList.Body>>(content);
listTracks.ItemsSource = items;
}
catch (Exception ex)
{
string exception = ex.Message;
}
}
The json from PostMan
{
"message": {
"header": {
"status_code": 200,
"execute_time": 0.013219118118286,
"available": 10000
},
"body": {
"track_list": [
{
"track": {
"track_id": 143296606,
"track_mbid": "",
"track_isrc": "",
"track_spotify_id": "",
"track_soundcloud_id": "",
"track_xboxmusic_id": "",
"track_name": "&Burn",
"track_name_translation_list": [],
"track_rating": 61,
"track_length": 179,
"commontrack_id": 79313332,
"instrumental": 0,
"explicit": 0,
"has_lyrics": 1,
"has_lyrics_crowd": 0,
"has_subtitles": 1,
"has_richsync": 1,
"num_favourite": 19,
"lyrics_id": 17324950,
"subtitle_id": 19405016,
"album_id": 27788309,
"album_name": "Dont Smile At Me",
"artist_id": 34955086,
"artist_mbid": "",
"artist_name": "Billie Eilish feat. Vince Staples",
"album_coverart_100x100": "http://s.mxmcdn.net/images-storage/albums/nocover.png",
"album_coverart_350x350": "",
"album_coverart_500x500": "",
"album_coverart_800x800": "",
"track_share_url": "https://www.musixmatch.com/lyrics/Billie-Eilish-feat-Vince-Staples/burn-with-Vince-Staples?utm_source=application&utm_campaign=api&utm_medium=IT+Related%3A1409617652911",
"track_edit_url": "https://www.musixmatch.com/lyrics/Billie-Eilish-feat-Vince-Staples/burn-with-Vince-Staples/edit?utm_source=application&utm_campaign=api&utm_medium=IT+Related%3A1409617652911",
"commontrack_vanity_id": "Billie-Eilish-feat-Vince-Staples/burn-with-Vince-Staples",
"restricted": 0,
"first_release_date": "2017-12-15T00:00:00Z",
"updated_time": "2017-12-17T22:53:56Z",
"primary_genres": {
"music_genre_list": []
},
"secondary_genres": {
"music_genre_list": []
}
}
}
]
}
}
}

Answer 1

You're telling it to deserialize the result to a list, when actually the result is object with 1 property (message) which has 2 properties (header and body), so make sure your object structure matches. I find json2csharp extremely handy for complex structures like this.
public class TrackListResponse
{
public Message message { get; set; }
public class Header
{
public int status_code { get; set; }
public double execute_time { get; set; }
public int available { get; set; }
}
public class PrimaryGenres
{
public List<object> music_genre_list { get; set; }
}
public class SecondaryGenres
{
public List<object> music_genre_list { get; set; }
}
public class Track
{
public int track_id { get; set; }
public string track_mbid { get; set; }
public string track_isrc { get; set; }
public string track_spotify_id { get; set; }
public string track_soundcloud_id { get; set; }
public string track_xboxmusic_id { get; set; }
public string track_name { get; set; }
public List<object> track_name_translation_list { get; set; }
public int track_rating { get; set; }
public int track_length { get; set; }
public int commontrack_id { get; set; }
public int instrumental { get; set; }
public int #explicit { get; set; }
public int has_lyrics { get; set; }
public int has_lyrics_crowd { get; set; }
public int has_subtitles { get; set; }
public int has_richsync { get; set; }
public int num_favourite { get; set; }
public int lyrics_id { get; set; }
public int subtitle_id { get; set; }
public int album_id { get; set; }
public string album_name { get; set; }
public int artist_id { get; set; }
public string artist_mbid { get; set; }
public string artist_name { get; set; }
public string album_coverart_100x100 { get; set; }
public string album_coverart_350x350 { get; set; }
public string album_coverart_500x500 { get; set; }
public string album_coverart_800x800 { get; set; }
public string track_share_url { get; set; }
public string track_edit_url { get; set; }
public string commontrack_vanity_id { get; set; }
public int restricted { get; set; }
public DateTime first_release_date { get; set; }
public DateTime updated_time { get; set; }
public PrimaryGenres primary_genres { get; set; }
public SecondaryGenres secondary_genres { get; set; }
}
public class TrackList
{
public Track track { get; set; }
}
public class Body
{
public List<TrackList> track_list { get; set; }
}
public class Message
{
public Header header { get; set; }
public Body body { get; set; }
}
}
Then just deserialize to the outer object:
JsonConvert.DeserializeObject<TrackListResponse>(content);

Answer 2

I think you can't deserialize a single object into a collection. So you should use TrackList.Body instead of List<TrackList.Body>
So you maybe have to change this line:
var items = JsonConvert.DeserializeObject<List<TrackList.Body>>(content);
to
var items = JsonConvert.DeserializeObject<TrackList.Body>(content);
then iterate each item in items to add them to a List<TrackList.Body>