Error: Newtonsoft.Json.JsonSerializationException

Question

您好，我正在学习使用Refit，遇到问题

这些是模型

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

        [JsonProperty("name")]
        public string Name { get; set; }
    }

    public partial class Article
    {
        [JsonProperty("source")]
        public Source Source { get; set; }

        [JsonProperty("author")]
        public string Author { get; set; }

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

        [JsonProperty("description")]
        public string Description { get; set; }

        [JsonProperty("url")]
        public Uri Url { get; set; }

        [JsonProperty("urlToImage")]
        public Uri UrlToImage { get; set; }

        [JsonProperty("publishedAt")]
        public DateTimeOffset PublishedAt { get; set; }

        [JsonProperty("content")]
        public string Content { get; set; }
    }

这是请求及其参数的接口。

    public interface IRest
    {
        [Get("/v2/top-headlines")]
        Task<List<Article>> GetArticles(string country, string apiKey"RemovingKey");
    }

这是 ArticleViewModel 中的请求

        private  async Task GetTaskAsync()
        {
            var WeApp = RestService.For<IRest>("https://newsapi.org/");
            var result = await WeApp.GetArticles("co");
        }

当我调试查看数据时出现

Newtonsoft.Json.JsonSerializationException
  Message=Cannot deserialize the current JSON object (e.g. {"name":"value"}) 
into type 'System.Collections.Generic.List`1[RefitNpt.Models.Article]'
 because the type requires a JSON array (e.g. [1,2,3]) to deserialize correctly.
To fix this error either change the JSON to a JSON array 
(e.g. [1,2,3]) or change the deserialized type so that it is a normal
 .NET type (e.g. not a primitive type like integer, not a collection type like an array or List<T>) 
that can be deserialized from a JSON object. 
JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object.
Path 'status', line 1, position 10.

我一直在寻找解决方案，但一直无法解决，我正在自学。

Answer 1

您需要另一个 class 作为您的 json 响应的 RootObject。

public class Articles
{
  public string status {get; set;}
  public int totalResults {get;set;}
  public List<Article> articles {get;set; }
}

然后在您的 IRest 控制器中使用它，（您需要将您的方法 (GetArticles) 更新为 return Articles 而不是 List<Article>。

Task<Articles> GetArticles(string country, string apiKey);

此回复与来自网站 https://newsapi.org

的以下 json 片段一致

{
  "status": "ok",
  "totalResults": 3152,
  "articles": [
    {
      "source": {
        "id": null,
        "name": "Business 2 Community"
      },
      "author": "Gurbaj Singh",
      "title": "Investing in Cryptocurrency? What are the Odds!?",
      "description": "Cryptocurrency has become the most profitable object for investing money. At the same time, in comparison with precious metals, natural…",
      "url": "https://www.business2community.com/finance/investing-in-cryptocurrency-what-are-the-odds-02326876",
      "urlToImage": "https://cdn.business2community.com/wp-content/uploads/2020/07/Untitled-design-3.png",
      "publishedAt": "2020-07-13T15:30:31Z",
      "content": "Cryptocurrency has become the most profitable object for investing money. At the same time, in comparison with precious metals, natural resources, or real estate, virtual coins involve more risks ass… [+9899 chars]"
    },
    // More Articles here...
  ]
}

Error: Newtonsoft.Json.JsonSerializationException

Error: Newtonsoft.Json.JsonSerializationException

c#

xamarin.forms

xamarin.android

refit