Cannot deserialize json result to custom list object using c#

c#, json, json.net

Solution

The JSON is valid, but you have an extra class that contains the list, so you'll need to break the class up like this:

public class positionsobj
{
    public positionlist positions { get; set; }
}

public class positionlist
{
    public List<position> position { get; set; }
}

public class position
{
    public float cost_basis { get; set; }
    public DateTime date_acquired { get; set; }
    public int id { get; set; }
    public decimal quantity { get; set; }
    public string symbol { get; set; }
}

And then decode them like this:

var responsebody = "{\"positions\":{\"position\":[{\"cost\":102.20000,\"date_acquired\":\"2013-11-18T19:54:13.730Z\",\"id\":192,\"quantity\":2.00000,\"symbol\":\"C\"},{\"cost\":121.50990,\"date_acquired\":\"2013-11-20T17:43:41.737Z\",\"id\":199,\"quantity\":1.00000,\"symbol\":\"TSLA\"}]}}";
positionsobj position = JsonConvert.DeserializeObject<positionsobj>(responsebody);

foreach (position item in position.positions.position)
{
     Console.WriteLine("Test : {0}", item.id);
}

But the class also had an extra problem in that `quantity` was a `decimal` and not a `int`. And your `Console.Write` was missing a `{0}` argument.

Problem

I have the below JSON: ``` {"positions":{"position":[{"cost_basis":102.20000,"date_acquired":"2013-11-18T19 :54:13.730Z","id":192,"quantity":2.00000,"symbol":"C"},{"cost_basis":121.50990," date_acquired":"2013-11-20T17:43:41.737Z","id":199,"quantity":1.00000,"symbol":" TSLA"}]}} ``` I am using JSON.NET (Newtonsoft package) in order to deserialize to my data object. ``` List<position> position = JsonConvert.DeserializeObject<List<position>>(responsebody); foreach (position item in listObj) { Console.WriteLine("Test : ", item.id); } public class positions { List<position> position { get; set; } } public class position { public float cost_basis { get; set; } public DateTime date_acquired { get; set; } public int id { get; set; } public int quantity { get; set; } public string symbol { get; set; } } ``` When I try to deserialize the object, I am getting the following error. ``` Unhandled Exception: Newtonsoft.Json.JsonSerializationException: Cannot deserial ize the current JSON object (e.g. {"name":"value"}) into type 'System.Collection s.Generic.List`1[ApiPost.position]' 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 chang e the deserialized type so that it is a normal .NET type (e.g. not a primitive t ype like integer, not a collection type like an array or List<T>) that can be de serialized from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object. Path 'positions', line 1, position 13. at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject(Js onReader reader, Type objectType, JsonContract contract, JsonProperty member, Js onContainerContract containerContract, JsonProperty containerMember, Object exis tingValue) at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInte rnal(JsonReader reader, Type objectType, JsonContract contract, JsonProperty mem ber, JsonContainerContract containerContract, JsonProperty containerMember, Obje ct existingValue) at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(Jso nReader reader, Type objectType, Boolean checkAdditionalContent) at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType) at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, Jso nSerializerSettings settings) at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSeriali zerSettings settings) ```

Original source