using System;

using System.Collections.Generic;

using System.Linq;

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

​

public static class JObjectExtensions

{

    public static IEnumerable<JProperty> SelectRootProperties(this JObject obj, params string[] propertyNames)

    {

        return obj.Children().OfType<JProperty>().Where(x => propertyNames.Contains(x.Name));       

    }

}

​

public class Program

{

    public static void Main()

    {

        var myJson = JObject.Parse(@"

          {

             ""channel"" :  ""nine"",

             ""segment"" :  ""mobile"",

             ""food"" :  ""pizza""

          }");

    var channelFoodNodes = myJson.SelectRootProperties("channel", "food");      

    var newObject = new JObject(channelFoodNodes);

    Console.WriteLine(newObject);

}

}