Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Deserializing JSON Object Array with Json.net

Tags:

c#

json.net

People also ask

Can not deserialize JSON array?

To fix this error either change the JSON to a JSON object (e.g. {"name":"value"}) or change the deserialized type to an array or a type that implements a collection interface (e.g. ICollection, IList) like List<T> that can be deserialized from a JSON array.


You can create a new model to Deserialize your JSON CustomerJson:

    public class CustomerJson
    {
        [JsonProperty("customer")]
        public Customer Customer { get; set; }
    }

    public class Customer
    {
        [JsonProperty("first_name")]
        public string Firstname { get; set; }

        [JsonProperty("last_name")]
        public string Lastname { get; set; }

        ...
    }

And you can deserialize your JSON easily:

JsonConvert.DeserializeObject<List<CustomerJson>>(json);

Documentation: Serializing and Deserializing JSON


For those who don't want to create any models, use the following code:

var result = JsonConvert.DeserializeObject<
  List<Dictionary<string, 
    Dictionary<string, string>>>>(content);

Note: This doesn't work for your JSON string. This is not a general solution for any JSON structure.


Using the accepted answer you have to access each record by using Customers[i].customer, and you need an extra CustomerJson class, which is a little annoying. If you don't want to do that, you can use the following:

public class CustomerList
{
    [JsonConverter(typeof(MyListConverter))]
    public List<Customer> customer { get; set; }
}

Note that I'm using a List<>, not an Array. Now create the following class:

class MyListConverter : JsonConverter
{
    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        var token = JToken.Load(reader);
        var list = Activator.CreateInstance(objectType) as System.Collections.IList;
        var itemType = objectType.GenericTypeArguments[0];
        foreach (var child in token.Values())
        {
            var childToken = child.Children().First();
            var newObject = Activator.CreateInstance(itemType);
            serializer.Populate(childToken.CreateReader(), newObject);
            list.Add(newObject);
        }
        return list;
    }

    public override bool CanConvert(Type objectType)
    {
        return objectType.IsGenericType && (objectType.GetGenericTypeDefinition() == typeof(List<>));
    }
    public override bool CanWrite => false;
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer) => throw new NotImplementedException();
}

Slight modification to what was stated above. My Json format, which validates was

{
    mycollection:{[
           {   
               property0:value,
               property1:value,
             },
             {   
               property0:value,
               property1:value,
             }
           ]

         }
       }

Using AlexDev's response, I did this Looping each child, creating reader from it

 public partial class myModel
{
    public static List<myModel> FromJson(string json) => JsonConvert.DeserializeObject<myModelList>(json, Converter.Settings).model;
}

 public class myModelList {
    [JsonConverter(typeof(myModelConverter))]
    public List<myModel> model { get; set; }

}

class myModelConverter : JsonConverter
{
    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        var token = JToken.Load(reader);
        var list = Activator.CreateInstance(objectType) as System.Collections.IList;
        var itemType = objectType.GenericTypeArguments[0];
        foreach (var child in token.Children())  //mod here
        {
            var newObject = Activator.CreateInstance(itemType);
            serializer.Populate(child.CreateReader(), newObject); //mod here
            list.Add(newObject);
        }
        return list;
    }

    public override bool CanConvert(Type objectType)
    {
        return objectType.IsGenericType && (objectType.GetGenericTypeDefinition() == typeof(List<>));
    }
    public override bool CanWrite => false;
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer) => throw new NotImplementedException();

}