新建NewtonsoftJsonSerializer.cs

/// <summary>
/// ISerializer implementation based on Newtonsoft.Json.
/// Default serializer used in calls to GetJsonAsync, PostJsonAsync, etc.
/// </summary>
public class NewtonsoftJsonSerializer : IJsonSerializer
{private readonly JsonSerializerSettings _settings;/// <summary>/// Initializes a new instance of the <see cref="NewtonsoftJsonSerializer"/> class./// </summary>/// <param name="settings">Settings to control (de)serialization behavior.</param>public NewtonsoftJsonSerializer(JsonSerializerSettings settings = null) {_settings = settings;}public string Serialize(object obj, Type type){return JsonConvert.SerializeObject(obj, _settings);}public object Deserialize(string json, Type type){return JsonConvert.DeserializeObject(json,type, _settings);}
}

代码修改为下面的即可