调用DeserializeObject <>时将引发Newtonsoft.Json.JsonReaderException

Question

对不起，因为我是新手。我正在尝试从Twitch获取流信息，无论该流是否为实时流。我通过使用HttpClient和GET请求来做到这一点。下面的类TwitchData将JSON反序列化为对象。

public partial class TwitchData
{
    [JsonProperty("data")]
    public Datum[] Data { get; set; }

    [JsonProperty("pagination")]
    public Pagination Pagination { get; set; }
}

public partial class Datum
{
    [JsonProperty("id")]
    public string Id { get; set; }

    [JsonProperty("user_id")]
    [JsonConverter(typeof(ParseStringConverter))]
    public long UserId { get; set; }

    [JsonProperty("game_id")]
    [JsonConverter(typeof(ParseStringConverter))]
    public long GameId { get; set; }

    [JsonProperty("community_ids")]
    public object[] CommunityIds { get; set; }

    [JsonProperty("type")]
    public string Type { get; set; }

    [JsonProperty("title")]
    public string Title { get; set; }

    [JsonProperty("viewer_count")]
    public long ViewerCount { get; set; }

    [JsonProperty("started_at")]
    public DateTimeOffset StartedAt { get; set; }

    [JsonProperty("language")]
    public string Language { get; set; }

    [JsonProperty("thumbnail_url")]
    public string ThumbnailUrl { get; set; }
}

public partial class Pagination
{
    [JsonProperty("cursor")]
    public string Cursor { get; set; }
}

public partial class TwitchData
{
    public static TwitchData FromJson(string json) => JsonConvert.DeserializeObject<TwitchData>(json, QuickType.Converter.Settings);
}

public static class Serialize
{
    public static string ToJson(this TwitchData self) => JsonConvert.SerializeObject(self, QuickType.Converter.Settings);
}

internal static class Converter
{
    public static readonly JsonSerializerSettings Settings = new JsonSerializerSettings
    {
        MetadataPropertyHandling = MetadataPropertyHandling.Ignore,
        DateParseHandling = DateParseHandling.None,
        Converters = {
            new IsoDateTimeConverter { DateTimeStyles = DateTimeStyles.AssumeUniversal }
        },
    };
}

internal class ParseStringConverter : JsonConverter
{
    public override bool CanConvert(Type t) => t == typeof(long) || t == typeof(long?);

    public override object ReadJson(JsonReader reader, Type t, object existingValue, JsonSerializer serializer)
    {
        if (reader.TokenType == JsonToken.Null) return null;
        var value = serializer.Deserialize<string>(reader);
        long l;
        if (Int64.TryParse(value, out l))
        {
            return l;
        }
        throw new Exception("Cannot unmarshal type long");
    }

    public override void WriteJson(JsonWriter writer, object untypedValue, JsonSerializer serializer)
    {
        if (untypedValue == null)
        {
            serializer.Serialize(writer, null);
            return;
        }
        var value = (long)untypedValue;
        serializer.Serialize(writer, value.ToString());
        return;
    }

    public static readonly ParseStringConverter Singleton = new ParseStringConverter();
}

我使用以下命令执行HttpClient GET请求

HttpClient client = new HttpClient();
string uri = "https://api.twitch.tv/helix/streams?user_id=59980349";
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Client-ID", token);
var result = client.GetStringAsync(uri);
jsonString = result.ToString();
twitchData = PwdResetRequest.FromJson(jsonString);

运行此命令时，将抛出Newtonsoft.Json.JsonReaderException, Unexpected character encountered while parsing value: S. Path '', line 0, position 0。进一步调试后，我发现程序在第71行

处中断

public static TwitchData FromJson(string json) => JsonConvert.DeserializeObject<TwitchData>(json, QuickType.Converter.Settings);

自从json2csharp.com获得此类以来，我不知道如何解决该问题，也不知道为什么抛出异常。

编辑：  注释中要求使用JSON。如果直播是直播的，这就是JSON

{
  "data": [
    {
      "id": "30356128676",
      "user_id": "59788312",
      "game_id": "498652",
      "community_ids": [],
      "type": "live",
      "title": "A stream",
      "viewer_count": 1325,
      "started_at": "2018-09-07T16:30:09Z",
      "language": "en",
      "thumbnail_url": "url"
    }
  ],
  "pagination": {
    "cursor": "eydBIjpwdWGsLaJhIjp7IkGH4hNl6CH6MXr9"
  }
}

及其离线状态

{
  "data": [],
  "pagination": {}
}