JSON.NET (Newtonsoft.Json) Custom converter

program.cs

using System;
using System.Collections.Generic;
using Newtonsoft.Json;
using Newtonsoft.Json.Converters;
using System.Runtime.Serialization;

namespace ConsoleApplication11
{
    [DataContract]
    public enum JsonPatchOperationType
    {
        [EnumMember(Value = "add")]
        Add = 0,

        [EnumMember(Value = "remove")]
        Remove = 1,

        [EnumMember(Value = "replace")]
        Replace = 2
    }

    public class JsonPatchOperation
    {
        [JsonConverter(typeof(StringEnumConverter))]
        public JsonPatchOperationType Operation { get; set; }
        public string PropertyName { get; set; }
        public object Value { get; set; }
    }

    [JsonConverter(typeof(JsonPatchDocumentConverter))]
    public class JsonPatchDocument
    {
        private readonly IEnumerable<JsonPatchOperation> _docs;

        public JsonPatchDocument(IEnumerable<JsonPatchOperation> docs)
        {
            _docs = docs;
        }

        public IEnumerable<JsonPatchOperation> Operations { get { return _docs; } }
    }

    // http://blog.maskalik.com/asp-net/json-net-implement-custom-serialization/
    public class JsonPatchDocumentConverter : JsonConverter
    {
        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
        {
            JsonPatchDocument jDoc = (JsonPatchDocument)value;
            serializer.Serialize(writer, jDoc.Operations);
        }

        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
        {
            throw new NotImplementedException();
        }

        public override bool CanConvert(Type objectType)
        {
            return typeof(JsonPatchDocument).IsAssignableFrom(objectType);
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            JsonPatchDocument jDoc = new JsonPatchDocument(new[]
            {
                new JsonPatchOperation
                {
                    Operation = JsonPatchOperationType.Add,
                    PropertyName = "/a/b/c",
                    Value = "foo"
                },

                new JsonPatchOperation
                {
                    Operation = JsonPatchOperationType.Remove,
                    PropertyName = "/a/foo",
                    Value = "bar"
                }
            });

            string result = JsonConvert.SerializeObject(jDoc);
        }
    }
}