c# - Json 对象到模型 MVC

Question

这是我的 Json 对象

{
  "id":5,
  "url":"http://localhost:8001/api/courses/5",
  "name":"Professional Experience II",
  "duration":"5.0",
  "description":"The course will talk in depth about every thing",
  "tutor": {
             "id":2,
             "email":"TA@mymail.com",
             "userName":"TA",
             "firstName":"T",
             "lastName":"A",
             "gender":0
           },
  "subject":
           {
             "id":2,
             "name":"Science"
           }
  }

我的模型在这里

public class CourseModel
    {
        public int Id { get; set; }
        public string Url { get; set; }
        public string Name { get; set; }
        public double Duration { get; set; }
        public string Description { get; set; }
        public TutorModel Tutor { get; set; }
        public SubjectModel Subject { get; set; }
    }

这就是我得到这个对象的方式。我能够获取 jsonObject 但无法将其反序列化为相应的模型

string url = "http://localhost:8001/api/courses/5";
HttpResponseMessage responseMessage = await client.GetAsync(url);
if (responseMessage.IsSuccessStatusCode)
{
  var responseData = responseMessage.Content.ReadAsStringAsync().Result;        
  var data = JsonConvert.DeserializeObject<List<CourseModel>>(responseData);
  return View(data);
}
return View("Error:);

我得到的错误是

Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.Collections.Generic.List`1[Learning.Web.Models.CourseModel]' 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) 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 'id', line 1, position 6.

我正在使用 WebApi，我不确定我在这里做错了什么。任何帮助将不胜感激

更新:

基于 Shyju 和 Habib 的回答，如果我将它反序列化为单个实例，它确实有效，但如果我将 url 更改为

string url = "http://localhost:8001/api/courses";

并将其反序列化为List，我得到同样的错误，这是json对象

   {  
       "totalCount":32,
       "totalPages":4,
       "prevPageLink":"",
       "nextPageLink":"http://localhost:8001/api/courses?page=1&pageSize=10",
       "results":[  
          {  
             "id":1,
             "url":"http://localhost:8001/api/courses/1",
             "name":"History Teaching Methods 1",
             "duration":3.0,
             "description":"The course will talk in depth about: History Teaching Methods 1",
             "tutor":{  
                "id":1,
                "email":"h@outlook.com",
                "userName":"A,
                "firstName":"A",
                "lastName":"J",
                "gender":0
             },
             "subject":{  
                "id":1,
                "name":"History"
             }
          },
          {  
             "id":2,
             "url":"http://localhost:8001/api/courses/2",
             "name":"History Teaching Methods 2",
             "duration":5.0,
             "description":"The course will talk in depth about: History Teaching Methods 2",
             "tutor":{  
                "id":1,
                "email":"A.Jo@fg.com",
                "userName":"AJo",
                "firstName":"A",
                "lastName":"Jo",
                "gender":0
             },
             "subject":{  
                "id":1,
                "name":"History"
             }
          },
          {  
             "id":3,
             "url":"http://localhost:8001/api/courses/3",
             "name":"History Teaching Methods 3",
             "duration":5.0,
             "description":"The course will talk in depth about: History Teaching Methods 3",
             "tutor":{  
                "id":1,
                "email":"A@outlook.com",
                "userName":"A",
                "firstName":"A",
                "lastName":"J",
                "gender":0
             },
             "subject":{  
                "id":1,
                "name":"History"
             }
          },
          {  
             "id":4,
             "url":"http://localhost:8001/api/courses/4",
             "name":"Professional Experience 1 (Mathematics/Science)",
             "duration":5.0,
             "description":"The course will talk in depth about: Professional Experience 1 (Mathematics/Science)",
             "tutor":{  
                "id":2,
                "email":"T.A@mymail.com",
                "userName":"T",
                "firstName":"T",
                "lastName":"A",
                "gender":0
             },
             "subject":{  
                "id":2,
                "name":"Science"
             }
          },
          {  
             "id":5,
             "url":"http://localhost:8001/api/courses/5",
             "name":"Professional Experience 2 (Mathematics/Science)",
             "duration":5.0,
             "description":"The course will talk in depth about: Professional Experience 2 (Mathematics/Science)",
             "tutor":{  
                "id":2,
                "email":"TA@mymail.com",
                "userName":"T",
                "firstName":"T",
                "lastName":"A",
                "gender":0
             },
             "subject":{  
                "id":2,
                "name":"Science"
             }
          },
          {  
             "id":6,
             "url":"http://localhost:8001/api/courses/6",
             "name":"Professional Experience 3 (Mathematics/Science)",
             "duration":5.0,
             "description":"The course will talk in depth about: Professional Experience 3 (Mathematics/Science)",
             "tutor":{  
                "id":2,
                "email":"TA@mymail.com",
                "userName":"T",
                "firstName":"T",
                "lastName":"A",
                "gender":0
             },
             "subject":{  
                "id":2,
                "name":"Science"
             }
          },
          {  
             "id":7,
             "url":"http://localhost:8001/api/courses/7",
             "name":"Geography Teaching Methods 1",
             "duration":5.0,
             "description":"The course will talk in depth about: Geography Teaching Methods 1",
             "tutor":{  
                "id":3,
                "email":"TW@mymail.com",
                "userName":"Ti",
                "firstName":"T",
                "lastName":"W",
                "gender":0
             },
             "subject":{  
                "id":3,
                "name":"Geography"
             }
          },
          {  
             "id":8,
             "url":"http://localhost:8001/api/courses/8",
             "name":"Geography Teaching Methods 2",
             "duration":5.0,
             "description":"The course will talk in depth about: Geography Teaching Methods 2",
             "tutor":{  
                "id":3,
                "email":"p@mymail.com",
                "userName":"f",
                "firstName":"f",
                "lastName":"f",
                "gender":0
             },
             "subject":{  
                "id":3,
                "name":"Geography"
             }
          },
          {  
             "id":9,
             "url":"http://localhost:8001/api/courses/9",
             "name":"Geography Teaching Methods 3",
             "duration":5.0,
             "description":"The course will talk in depth about: Geography Teaching Methods 3",
             "tutor":{  
                "id":3,
                "email":"s.s@mymail.com",
                "userName":"s",
                "firstName":"s",
                "lastName":"s",
                "gender":0
             },
             "subject":{  
                "id":3,
                "name":"Geography"
             }
          },
          {  
             "id":10,
             "url":"http://localhost:8001/api/courses/10",
             "name":"English Education 1",
             "duration":5.0,
             "description":"The course will talk in depth about: English Education 1",
             "tutor":{  
                "id":4,
                "email":"g.g@outlook.com",
                "userName":"g",
                "firstName":"g",
                "lastName":"g",
                "gender":0
             },
             "subject":{  
                "id":4,
                "name":"English"
             }
          }
       ]
    }

Answer 1

您的 JSON 表示 CourseModel 的单个实例。您应该将其反序列化为 CourseModel 的单个实例，而不是这些实例的列表。

这应该有效。

var data = JsonConvert.DeserializeObject<CourseModel>(responseData);