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    <p>Use <code>CustomCreationConverter&lt;T&gt;</code> as JsonConverter and override both <code>Create</code> and <code>ReadJson</code> method.</p> <pre><code>class ItemConverter : CustomCreationConverter&lt;Item&gt; { public override Item Create(Type objectType) { return new Item(); } public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer) { JObject jObject = JObject.Load(reader); int categoryId = jObject["categoryId"].ToObject&lt;int&gt;(); Category category = Program.Repository.GetCategoryById(categoryId); Item result = (Item)base.ReadJson(jObject.CreateReader(), objectType, existingValue, serializer); result.Category = category; return result; } } class Item { [JsonProperty("itemName")] public string ItemName { get; set; } public Category Category { get; set; } // other properties. } class Category { public int CategoryId { get; set; } public string Name { get; set; } // other properties. } class MockCategoryRepository { IList&lt;Category&gt; _repository; public MockCategoryRepository() { _repository = new List&lt;Category&gt;(); _repository.Add(new Category() { CategoryId = 1, Name = "Drink" }); _repository.Add(new Category() { CategoryId = 35, Name = "Food" }); _repository.Add(new Category() { CategoryId = 70, Name = "Fruit" }); } public Category GetCategoryById(int id) { return _repository.Where(x =&gt; x.CategoryId == id).SingleOrDefault(); } } class Program { public static MockCategoryRepository Repository { get; private set; } static void Main(string[] args) { Repository = new MockCategoryRepository(); // initialize mock repository // sample : json contains two items in an array. string jsonString = @" [ { ""categoryId"":""35"", ""itemName"":""Item A"" }, { ""categoryId"":""70"", ""itemName"":""Item B"" }, ]"; List&lt;Item&gt; items = JsonConvert.DeserializeObject&lt;List&lt;Item&gt;&gt;(jsonString, new ItemConverter()); } } </code></pre> <h2>Updated answer :</h2> <p>Solution for condition where <code>Category</code> object information is fetched from the same json string.</p> <pre><code>class ItemConverter : CustomCreationConverter&lt;Item&gt; { readonly IEnumerable&lt;Category&gt; _repository; public ItemConverter(IEnumerable&lt;Category&gt; categories) { _repository = categories; } public override Item Create(Type objectType) { return new Item(); } public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer) { JObject jObject = JObject.Load(reader); int categoryId = jObject["categoryId"].ToObject&lt;int&gt;(); Category category = _repository.Where(x =&gt; x.CategoryId == categoryId).SingleOrDefault(); Item result = (Item)base.ReadJson(jObject.CreateReader(), objectType, existingValue, serializer); result.Category = category; return result; } } class Item { [JsonProperty("name")] public string Name { get; set; } public Category Category { get; set; } // other properties. } class Category { [JsonProperty("id")] public int CategoryId { get; set; } [JsonProperty("name")] public string Name { get; set; } // other properties. } class Program { static void Main(string[] args) { // sample : json contains items and/or categories in an array. string jsonString = @" [ { ""id"" : ""2"", ""categoryId"" : ""35"", ""type"" : ""item"", ""name"" : ""hamburger"" }, { ""id"" : ""35"", ""type"" : ""category"", ""name"" : ""drinks"" } ]"; JArray jsonArray = JArray.Parse(jsonString); // Separate between category and item data. IEnumerable&lt;JToken&gt; jsonCategories = jsonArray.Where(x =&gt; x["type"].ToObject&lt;string&gt;() == "category"); IEnumerable&lt;JToken&gt; jsonItems = jsonArray.Where(x =&gt; x["type"].ToObject&lt;string&gt;() == "item"); // Create list of category from jsonCategories. IEnumerable&lt;Category&gt; categories = jsonCategories.Select(x =&gt; x.ToObject&lt;Category&gt;()); // Settings for jsonItems deserialization. JsonSerializerSettings itemDeserializerSettings = new JsonSerializerSettings(); itemDeserializerSettings.Converters.Add(new ItemConverter(categories)); JsonSerializer itemDeserializer = JsonSerializer.Create(itemDeserializerSettings); // Create list of item from jsonItems. IEnumerable&lt;Item&gt; items = jsonItems.Select(x =&gt; x.ToObject&lt;Item&gt;(itemDeserializer)); } } </code></pre>
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    1. POHow to use custom reference resolving with JSON.NET
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    1. USKhairuddin Ni'am
    1. USKhairuddin Ni'am
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    1. COBut if a Category is defined elsewhere in the master JSON file, then wouldn't duplicate instances be created for the same Category identity?
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      1. USMichael Hedgpeth
    2. CONo, because in my sample (in-memory repository), `GetCategoryById` only do searching, not creating new `Category` object. Yes, if your repository is getting information from database (real-life case). All you need is to modify get category algorithm on `ReadJson` method to solve your problem.
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      1. USKhairuddin Ni'am
    3. COIf that was the case, then when a category was created by the JSON deserializer, it would have to be registered with the repository, or when it tried to create one that was already referenced, it would have to use the existing Category instance, correct? I don't see how your solution solves those two issues.
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      1. USMichael Hedgpeth
 

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