Generic Pattern: Cannot deserialize the JSON array

Question

I am trying to write a generic pattern to deserialize my json array string. i have the following object created bellow:

public interface IDataResponse<T> where T: class
{
    List<T> Data { get; set; }
}

public class DataResponse<T>: IDataResponse<T> where T: class
{
    [JsonProperty("value")]
    public List<T> Data { get; set; }
}

My json format

{  
   "values":{  
   "value":[  
     {  
        "value_1":"aaaaaa",
        "value_2":"aaaaaa",
        "value_3":"aaaaaa"
     },
     {  
        "value_1":"bbbbbb",
        "value_2":"bbbbbb",
        "value_3":"bbbbbb"
     }
  ]
  }
}

Now i can use this pattern like that

var myData = JsonConvert.DeserializeObject<List<DataResponse<MyData>>>(result);

where result is the json array string.

But ruuning this code , i got the exception bellow

Cannot deserialize the JSON array (e.g. [1,2,3]) into type ' ' because type requires JSON object (e.g. {“name”:“value”}) to deserialize correctly

How cani fix this error?

Mathieu · Accepted Answer · 2016-08-22 14:43:49Z

I'm not sure to well understand but, Haven't you missed the parent container of your list ?

I share you a code to desrialize your data

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            string result = @"
{  
   'values':{  
   'value':[
     {  
        'value_1':'aaaaaa',
        'value_2':'aaaaaa',
        'value_3':'aaaaaa'
     },
     {  
        'value_1':'bbbbbb',
        'value_2':'bbbbbb',
        'value_3':'bbbbbb'
     }
  ]
  }
}";

            var myData = JsonConvert.DeserializeObject<MyContent<MyData>>(result);
        }
    }

    public class MyContent<T> where T : class
    {

        [JsonProperty("values")]
        public DataResponse<T> Values { get; set; }
    }

    [Serializable]
    public class MyData
    {
        public string value_1 { get; set; }
        public string value_2 { get; set; }
        public string value_3 { get; set; }
    }

    public interface IDataResponse<T> where T : class
    {
        List<T> Data { get; set; }
    }

    public class DataResponse<T> : IDataResponse<T> where T : class
    {
        [JsonProperty("value")]
        public List<T> Data { get; set; }
    }
}

fknx · Accepted Answer · 2016-08-22 14:51:56Z

0

The error message indicates that there is no matching class for the values part of your json data. You need to change the structure of your json or you'll have to add another (root) class:

public class DataRoot<T> where T : class
{
    public DataResponse<T> Values { get; set;}
}

public interface IDataResponse<T> where T : class
{
    List<T> Data { get; set; }
}

public class DataResponse<T> : IDataResponse<T> where T : class
{
    [JsonProperty("value")]
    public List<T> Data { get; set; }
}

Then you can get your data like this:

var myData = JsonConvert.DeserializeObject<DataRoot<MyData>>(result).Values;

answered Aug 22, 2016 at 14:51

fknx

1,78514 silver badges20 bronze badges

Collectives™ on Stack Overflow

Generic Pattern: Cannot deserialize the JSON array

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related