无法反序列化当前 JSON 对象 xamarin.forms
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【中文标题】无法反序列化当前 JSON 对象 xamarin.forms【英文标题】：Cannot deserialize the current JSON object xamarin.forms 【发布时间】：2018-04-11 09:57:00 【问题描述】：我正在使用 xamarin.forms 创建一个使用 MusixMatch api 的应用程序。它抛出以下异常：无法将当前 JSON 对象（例如 \"name\":\"value\"）反序列化为类型 'System.Collections.Generic.List。据我所知，我所做的一切都是正确的，不知道为什么会抛出这个异常。任何帮助将不胜感激。
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 请求
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;
来自 PostMan 的 json
"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": []
]
【问题讨论】：
您是否刚刚在公共网站上发布了您的 API 密钥..？也许不是最好的事情:) 我通常从app.quicktype.io 开始，然后生成一个类，然后按照我想要的方式更改命名 糟糕，忘记了。感谢你。会尝试你的建议 您的 api 密钥仍在问题历史记录中。 看起来您尝试序列化的类型与 JSON 结构不匹配。 【参考方案1】：您告诉它将结果反序列化为列表，而实际上结果是具有 1 个属性（消息）的对象，该对象具有 2 个属性（标题和正文），因此请确保您的对象结构匹配。我发现 json2csharp 对于像这样的复杂结构非常方便。
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;
然后只需反序列化到外部对象：
JsonConvert.DeserializeObject<TrackListResponse>(content);
【讨论】：
谢谢你:)。我已经尝试过了，但属性在“项目”中返回 null，但值已成功传递给“内容” 我第一次可能把 body 对象弄错了一点。答案已更新 - json2csharp 来救援。 :) 非常感谢托德：D。现在可以了。只是属性现在没有绑定到我的 xaml，但我会弄清楚的。谢谢【参考方案2】：我认为您不能将单个对象反序列化为集合。所以你应该使用TrackList.Body 而不是List<TrackList.Body>
所以你可能不得不改变这一行：
var items = JsonConvert.DeserializeObject<List<TrackList.Body>>(content);
到
var items = JsonConvert.DeserializeObject<TrackList.Body>(content);
然后迭代items 中的每个项目以将它们添加到List<TrackList.Body>
【讨论】：
谢谢。我已经尝试过了，异常消失了，但现在“items”返回 null，即使在调试时我可以看到响应状态为 200 并传递给“content” 我已经更新了我的帖子以包含 json 以便更好地理解以上是关于无法反序列化当前 JSON 对象 xamarin.forms的主要内容，如果未能解决你的问题，请参考以下文章
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