C# – Deserializing JSON Object Array with Json.net

cjson.net

I am attempt to use an API that use the follow example structure for their returned json

[
   {
      "customer":{
         "first_name":"Test",
         "last_name":"Account",
         "email":"test1@example.com",
         "organization":"",
         "reference":null,
         "id":3545134,
         "created_at":"2013-08-06T15:51:15-04:00",
         "updated_at":"2013-08-06T15:51:15-04:00",
         "address":"",
         "address_2":"",
         "city":"",
         "state":"",
         "zip":"",
         "country":"",
         "phone":""
      }
   },
   {
      "customer":{
         "first_name":"Test",
         "last_name":"Account2",
         "email":"test2@example.com",
         "organization":"",
         "reference":null,
         "id":3570462,
         "created_at":"2013-08-12T11:54:58-04:00",
         "updated_at":"2013-08-12T11:54:58-04:00",
         "address":"",
         "address_2":"",
         "city":"",
         "state":"",
         "zip":"",
         "country":"",
         "phone":""
      }
   }
]

JSON.net would work great with something like the following structure

{
    "customer": {
        ["field1" : "value", etc...],
        ["field1" : "value", etc...],
    }
}

But I can not figure out how to get it to be happy with the provided structure.

Using the default JsonConvert.DeserializeObject(content) results the correct number of Customer but all of the data is null.

Doing something a CustomerList (below) results in a "Cannot deserialize the current JSON array" exception

public class CustomerList
{
    public List<Customer> customer { get; set; }
}

Thoughts?

Best Answer

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

Related Solutions

C# – JavaScriptSerializer – JSON serialization of enum as string

I have found that Json.NET provides the exact functionality I'm looking for with a StringEnumConverter attribute:

using Newtonsoft.Json;
using Newtonsoft.Json.Converters;

[JsonConverter(typeof(StringEnumConverter))]
public Gender Gender { get; set; }

More details at available on StringEnumConverter documentation.

There are other places to configure this converter more globally:

enum itself if you want enum always be serialized/deserialized as string:

[JsonConverter(typeof(StringEnumConverter))]  
enum Gender { Male, Female }

In case anyone wants to avoid attribute decoration, you can add the converter to your JsonSerializer (suggested by Bjørn Egil):
```
serializer.Converters.Add(new Newtonsoft.Json.Converters.StringEnumConverter()); 
```
and it will work for every enum it sees during that serialization (suggested by Travis).

or JsonConverter (suggested by banana):

JsonConvert.SerializeObject(MyObject, 
    new Newtonsoft.Json.Converters.StringEnumConverter());

Additionally you can control casing and whether numbers are still accepted by using StringEnumConverter(NamingStrategy, Boolean) constructor.

C# – Deserialize JSON into C# dynamic object

If you are happy to have a dependency upon the System.Web.Helpers assembly, then you can use the Json class:

dynamic data = Json.Decode(json);

It is included with the MVC framework as an additional download to the .NET 4 framework. Be sure to give Vlad an upvote if that's helpful! However if you cannot assume the client environment includes this DLL, then read on.

An alternative deserialisation approach is suggested here. I modified the code slightly to fix a bug and suit my coding style. All you need is this code and a reference to System.Web.Extensions from your project:

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Dynamic;
using System.Linq;
using System.Text;
using System.Web.Script.Serialization;

public sealed class DynamicJsonConverter : JavaScriptConverter
{
    public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
    {
        if (dictionary == null)
            throw new ArgumentNullException("dictionary");

        return type == typeof(object) ? new DynamicJsonObject(dictionary) : null;
    }

    public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
    {
        throw new NotImplementedException();
    }

    public override IEnumerable<Type> SupportedTypes
    {
        get { return new ReadOnlyCollection<Type>(new List<Type>(new[] { typeof(object) })); }
    }

    #region Nested type: DynamicJsonObject

    private sealed class DynamicJsonObject : DynamicObject
    {
        private readonly IDictionary<string, object> _dictionary;

        public DynamicJsonObject(IDictionary<string, object> dictionary)
        {
            if (dictionary == null)
                throw new ArgumentNullException("dictionary");
            _dictionary = dictionary;
        }

        public override string ToString()
        {
            var sb = new StringBuilder("{");
            ToString(sb);
            return sb.ToString();
        }

        private void ToString(StringBuilder sb)
        {
            var firstInDictionary = true;
            foreach (var pair in _dictionary)
            {
                if (!firstInDictionary)
                    sb.Append(",");
                firstInDictionary = false;
                var value = pair.Value;
                var name = pair.Key;
                if (value is string)
                {
                    sb.AppendFormat("{0}:\"{1}\"", name, value);
                }
                else if (value is IDictionary<string, object>)
                {
                    new DynamicJsonObject((IDictionary<string, object>)value).ToString(sb);
                }
                else if (value is ArrayList)
                {
                    sb.Append(name + ":[");
                    var firstInArray = true;
                    foreach (var arrayValue in (ArrayList)value)
                    {
                        if (!firstInArray)
                            sb.Append(",");
                        firstInArray = false;
                        if (arrayValue is IDictionary<string, object>)
                            new DynamicJsonObject((IDictionary<string, object>)arrayValue).ToString(sb);
                        else if (arrayValue is string)
                            sb.AppendFormat("\"{0}\"", arrayValue);
                        else
                            sb.AppendFormat("{0}", arrayValue);

                    }
                    sb.Append("]");
                }
                else
                {
                    sb.AppendFormat("{0}:{1}", name, value);
                }
            }
            sb.Append("}");
        }

        public override bool TryGetMember(GetMemberBinder binder, out object result)
        {
            if (!_dictionary.TryGetValue(binder.Name, out result))
            {
                // return null to avoid exception.  caller can check for null this way...
                result = null;
                return true;
            }

            result = WrapResultObject(result);
            return true;
        }

        public override bool TryGetIndex(GetIndexBinder binder, object[] indexes, out object result)
        {
            if (indexes.Length == 1 && indexes[0] != null)
            {
                if (!_dictionary.TryGetValue(indexes[0].ToString(), out result))
                {
                    // return null to avoid exception.  caller can check for null this way...
                    result = null;
                    return true;
                }

                result = WrapResultObject(result);
                return true;
            }

            return base.TryGetIndex(binder, indexes, out result);
        }

        private static object WrapResultObject(object result)
        {
            var dictionary = result as IDictionary<string, object>;
            if (dictionary != null)
                return new DynamicJsonObject(dictionary);

            var arrayList = result as ArrayList;
            if (arrayList != null && arrayList.Count > 0)
            {
                return arrayList[0] is IDictionary<string, object> 
                    ? new List<object>(arrayList.Cast<IDictionary<string, object>>().Select(x => new DynamicJsonObject(x))) 
                    : new List<object>(arrayList.Cast<object>());
            }

            return result;
        }
    }

    #endregion
}

You can use it like this:

string json = ...;

var serializer = new JavaScriptSerializer();
serializer.RegisterConverters(new[] { new DynamicJsonConverter() });

dynamic obj = serializer.Deserialize(json, typeof(object));

So, given a JSON string:

{
  "Items":[
    { "Name":"Apple", "Price":12.3 },
    { "Name":"Grape", "Price":3.21 }
  ],
  "Date":"21/11/2010"
}

The following code will work at runtime:

dynamic data = serializer.Deserialize(json, typeof(object));

data.Date; // "21/11/2010"
data.Items.Count; // 2
data.Items[0].Name; // "Apple"
data.Items[0].Price; // 12.3 (as a decimal)
data.Items[1].Name; // "Grape"
data.Items[1].Price; // 3.21 (as a decimal)

Best Answer

Related Solutions

C# – JavaScriptSerializer – JSON serialization of enum as string

C# – Deserialize JSON into C# dynamic object

Related Topic