using System;

using System.Linq;

using Newtonsoft.Json.Linq;

public static class Program

{

    public static JObject FindDiff(JToken Current, JToken Model)

    {

        JObject diff = new JObject();

        if (JToken.DeepEquals(Current, Model)) return diff;

​

        switch(Current.Type)

        {

            case JTokenType.Object:

                {

                    var current = Current as JObject;

                    var model = Model as JObject;

                    var addedKeys = current.Properties().Select(c => c.Name).Except(model.Properties().Select(c => c.Name));

                    var removedKeys = model.Properties().Select(c => c.Name).Except(current.Properties().Select(c => c.Name));

                    var unchangedKeys = current.Properties().Where(c => JToken.DeepEquals(c.Value, Model[c.Name])).Select(c => c.Name);

                    foreach (var k in addedKeys)

                    {

                        diff["+"] = new JObject

                        {

                            {"+", Current[k]}

                        };

                    }

                    foreach (var k in removedKeys)

                    {

                        diff[k] = new JObject

                        {

                            {"-",  Model[k]}

                        };

                    }

                    var potentiallyModifiedKeys = current.Properties().Select(c => c.Name).Except(addedKeys).Except(unchangedKeys);

                    foreach (var k in potentiallyModifiedKeys)

                    {

                        var foundDiff = FindDiff(current[k], model[k]);

                        if(foundDiff.HasValues) diff[k] = foundDiff;

                    }

                }

                break;

            case JTokenType.Array:

                {

                    var current = Current as JArray;

                    var model = Model as JArray;

                    var plus = new JArray(current.Except(model, new JTokenEqualityComparer()));

                    var minus = new JArray(model.Except(current, new JTokenEqualityComparer()));

                    if (plus.HasValues) diff["+"] = plus;

                    if (minus.HasValues) diff["-"] = minus;

                }

                break;

            default:

                diff["+"] = Current;

                diff["-"] = Model;

                break;

        }

​

        return diff;

    }

    public static void Main()

    {

        JObject o1 = new JObject

        {

            { "Integer", 1234 },

            { "String", "A string" },

            { "Items", new JArray(1, 2) }

        };

​

        JObject o2 = new JObject

        {

            { "Integer", 12345 },

            { "String", "A string" },

            { "Items", new JArray(1, 2) }

        };

        JObject diff = FindDiff(o1, o2);

        Console.WriteLine(Newtonsoft.Json.JsonConvert.SerializeObject( diff ));

    }

}