76

In my web app I'm using Newtonsoft.Json and I have following object

[Newtonsoft.Json.JsonObject(Title = "MyCar")]
public class Car
{
    [Newtonsoft.Json.JsonProperty(PropertyName = "name")]
    public string Name{get;set;}

    [Newtonsoft.Json.JsonProperty(PropertyName = "owner")]
    public string Owner{get;set;}
}

and I want serialize them with root name (class name). This is desired format using

{'MyCar':
 {
   'name': 'Ford',
   'owner': 'John Smith'
 }
}

I know that I can do that with anonymous object, but is any property or another way in Newtonsoft.Json library?

Andrei
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user2034092
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11 Answers11

43

Use anonymous class

Shape your model the way you want using anonymous classes:

var root = new 
{ 
    car = new 
    { 
        name = "Ford", 
        owner = "Henry"
    }
};

string json = JsonConvert.SerializeObject(root);
Andrei
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  • How can I achieve the same If I am taking object as input in a method that has JsonConvert.SerializeObject. `public void SendMessage(object someObject) { JsonConvert.SerializeObject(someObject); }` In this case, everytime root element will be "someObject" and not the needed name. – RonakThakkar Feb 05 '16 at 12:59
  • Where can I find "RootFormatter" class? Which namespace I have to include here? – alok_dida Apr 09 '18 at 22:39
  • @alok_dida seems like it's something very old, I can't find it now - I'll remove this part. Thanks – Andrei Apr 10 '18 at 08:24
41

I found an easy way to render this out... simply declare a dynamic object and assign the first item within the dynamic object to be your collection class...This example assumes you're using Newtonsoft.Json

private class YourModelClass
{
    public string firstName { get; set; }
    public string lastName { get; set; }
}

var collection = new List<YourModelClass>();

var collectionWrapper = new {

    myRoot = collection

};

var output = JsonConvert.SerializeObject(collectionWrapper);

What you should end up with is something like this:

{"myRoot":[{"firstName":"John", "lastName": "Citizen"}, {...}]}
Andrei
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Matthew Merryfull
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  • if we return string ... in result show extra quotations... that should be removed .... by this link http://forums.asp.net/t/1821728.aspx?Web+API+project+returning+JSON+issues – saber tabatabaee yazdi Sep 12 '15 at 15:09
  • This works. I was looking for something like this to avoid having to declare a wrapper `RootObject` class. – Shiva Feb 15 '17 at 20:44
  • What is `myRoot`? – Delfino Feb 21 '18 at 16:47
  • @Delfino `myRoot` is just an abitrary string, you can specify anything you want there. – Matthew Merryfull Feb 26 '18 at 23:10
  • This worked to give me a list that was compatible with JsonConfig, to read into a collection from a JsonConfig config file (settings.conf) after a small amount of find-and-replace editing. I could RegEx it to this form if I needed the whole thing repeatedly automated. This was what I was after in the JsonConfig settings file: TestsToRun:["MySpecFlowXunitTest1.dll","MySpecFlowXunitTestOther.dll","MySpecFlowXunitTestYetAnother.dll"] and then this C# line reads them using JsonConfig: List allowedTestsList = Config.Global.TestsToRun; – Developer63 Apr 27 '19 at 04:54
13

You can easily create your own serializer

var car = new Car() { Name = "Ford", Owner = "John Smith" };
string json = Serialize(car);

string Serialize<T>(T o)
{
    var attr = o.GetType().GetCustomAttribute(typeof(JsonObjectAttribute)) as JsonObjectAttribute;

    var jv = JValue.FromObject(o);

    return new JObject(new JProperty(attr.Title, jv)).ToString();
}
I4V
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8

Sorry, my english is not that good. But i like to improve the upvoted answers. I think that using Dictionary is more simple and clean.

class Program
    {
        static void Main(string[] args)
        {
            agencia ag1 = new agencia()
            {
                name = "Iquique",
                data = new object[] { new object[] {"Lucas", 20 }, new object[] {"Fernando", 15 } }
            };
            agencia ag2 = new agencia()
            {
                name = "Valparaiso",
                data = new object[] { new object[] { "Rems", 20 }, new object[] { "Perex", 15 } }
            };
            agencia agn = new agencia()
            {
                name = "Santiago",
                data = new object[] { new object[] { "Jhon", 20 }, new object[] { "Karma", 15 } }
            };


            Dictionary<string, agencia> dic = new Dictionary<string, agencia>
            {
                { "Iquique", ag1 },
                { "Valparaiso", ag2 },
                { "Santiago", agn }
            };

            string da = Newtonsoft.Json.JsonConvert.SerializeObject(dic);

            Console.WriteLine(da);
            Console.ReadLine();
        }


    }

    public class agencia
    {
        public string name { get; set; }
        public object[] data { get; set; }
    }

This code generate the following json (This is desired format)

{  
   "Iquique":{  
      "name":"Iquique",
      "data":[  
         [  
            "Lucas",
            20
         ],
         [  
            "Fernando",
            15
         ]
      ]
   },
   "Valparaiso":{  
      "name":"Valparaiso",
      "data":[  
         [  
            "Rems",
            20
         ],
         [  
            "Perex",
            15
         ]
      ]
   },
   "Santiago":{  
      "name":"Santiago",
      "data":[  
         [  
            "Jhon",
            20
         ],
         [  
            "Karma",
            15
         ]
      ]
   }
}
user2440841
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4
string Json = JsonConvert.SerializeObject(new Car { Name = "Ford", Owner = "John Smith" }, Formatting.None);

for the root element use GlobalConfiguration.

Newton Sheikh
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4

A very simple approach for me is just to create 2 classes.

public class ClassB
{
    public string id{ get; set; }
    public string name{ get; set; }
    public int status { get; set; }
    public DateTime? updated_at { get; set; }
}

public class ClassAList
{
    public IList<ClassB> root_name{ get; set; } 
}

And when you going to do serialization:

var classAList = new ClassAList();
//...
//assign some value
//...
var jsonString = JsonConvert.SerializeObject(classAList)

Lastly, you will see your desired result as the following:

{
  "root_name": [
    {
      "id": "1001",
      "name": "1000001",
      "status": 1010,
      "updated_at": "2016-09-28 16:10:48"
    },
    {
      "id": "1002",
      "name": "1000002",
      "status": 1050,
      "updated_at": "2016-09-28 16:55:55"
    }
  ]
}

Hope this helps!

Js Yau
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jet_choong
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3

Well, you can at least tell Json.NET to include the type name: http://www.newtonsoft.com/json/help/html/T_Newtonsoft_Json_TypeNameHandling.htm . Newtonsoft.Json.JsonSerializer jser = new Newtonsoft.Json.JsonSerializer(); jser.TypeNameHandling = TypeNameHandling.Objects;

The type will be included at the beginning in the "$type" property of the object.

This is not exactly what you are looking for, but it was good enough for me when facing a similiar problem.

2

Writing a custom JsonConverter is another approach mentioned in similar questions. However, due to nature of how JsonConverter is designed, using that approach for this question is tricky, as you need to be careful with the WriteJson implementation to avoid getting into infinite recursion: JSON.Net throws StackOverflowException when using [JsonConvert()].

One possible implementation:

public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
    //JToken t = JToken.FromObject(value); // do not use this! leads to stack overflow
    JsonObjectContract contract = (JsonObjectContract)serializer.ContractResolver.ResolveContract(value.GetType());

    writer.WriteStartObject();
    writer.WritePropertyName(value.GetType().Name);
    writer.WriteStartObject();
    foreach (var property in contract.Properties)
    {
        // this removes any property with null value
        var propertyValue = property.ValueProvider.GetValue(value);
        if (propertyValue == null) continue;

        writer.WritePropertyName(property.PropertyName);
        serializer.Serialize(writer, propertyValue);
        //writer.WriteValue(JsonConvert.SerializeObject(property.ValueProvider.GetValue(value))); // this adds escaped quotes
    }
    writer.WriteEndObject();
    writer.WriteEndObject();
}
prusswan
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1

I hope this help.

//Sample of Data Contract:

[DataContract(Name="customer")]
internal class Customer {
  [DataMember(Name="email")] internal string Email { get; set; }
  [DataMember(Name="name")] internal string Name { get; set; }
}

//This is an extension method useful for your case:

public static string JsonSerialize<T>(this T o)
{
  MemoryStream jsonStream = new MemoryStream();
  var serializer = new System.Runtime.Serialization.Json.DataContractJsonSerializer(typeof(T));
  serializer.WriteObject(jsonStream, o);

  var jsonString = System.Text.Encoding.ASCII.GetString(jsonStream.ToArray());

  var props = o.GetType().GetCustomAttributes(false);
  var rootName = string.Empty;
  foreach (var prop in props)
  {
    if (!(prop is DataContractAttribute)) continue;
    rootName = ((DataContractAttribute)prop).Name;
    break;
  }
  jsonStream.Close();
  jsonStream.Dispose();

  if (!string.IsNullOrEmpty(rootName)) jsonString = string.Format("{{ \"{0}\": {1} }}", rootName, jsonString);
  return jsonString;
}

//Sample of usage

var customer = new customer { 
Name="John",
Email="john@domain.com"
};
var serializedObject = customer.JsonSerialize();
0

You can use a dictionary too and even better add a method to the class itself:

public class Car
{
    [Newtonsoft.Json.JsonProperty(PropertyName = "name")]
    public string Name{get;set;}

    [Newtonsoft.Json.JsonProperty(PropertyName = "owner")]
    public string Owner{get;set;}

    public string ToJson(string rootName)
    {            
        var dictionary = new Dictionary<string, Car>
        {
            { rootName, this }
        };

        return JsonConvert.SerializeObject(dictionary);
    }
}

// Use:
var car = new Car()
{ 
    Name = "Ford", 
    Owner = "Henry"
};

car.ToJson("myCar");
Vanderlei Morais
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-5
[Newtonsoft.Json.JsonObject(Title = "root")]
public class TestMain

this is the only attrib you need to add to get your code working.

Andrei
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gmuonio
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