JObject & CamelCase conversion with JSON.Net

Question

How can I convert a generic JObject to camelCase plain json string? I've tried with JsonSerializerSettings but doesn't work (Newtonsoft.Json 4.5.11)

[Test] public void should_convert_to_camel_case() {     var serializer = JsonSerializer.Create(new JsonSerializerSettings()     {         ContractResolver = new CamelCasePropertyNamesContractResolver()     });      var jo = new JObject();     jo["CamelCase"] = 1;      var stringWriter = new StringWriter();     var writer = new JsonTextWriter(stringWriter);     serializer.Serialize(writer,jo);      var serialized = stringWriter.ToString();      Assert.AreEqual("{\"camelCase\":1}", serialized); } 

UPDATE According to http://json.codeplex.com/workitem/23853 that cannot be done (tnx to @nick_w for the link)

Answer 1

This question starts from a JObject and wants to work to a camel-cased JSON object. If you are actually starting from an object and want to get to a JObject that is already camelcased, then you can do this:

var serializer = new JsonSerializer() {     ContractResolver = new CamelCasePropertyNamesContractResolver() }; var jo = JObject.FromObject(someDataContract, serializer); 

The resulting 'jo' will be camelcased.

Answer 2

According to this Json.NET issue, when serializing a JObject this way the contract resolver is ignored:

When serializing a JObject the contract resolvers seems to be ignored. Surely this is not how it is supposed to be?
Closed Jan 30, 2013 at 8:50 AM by JamesNK
That does make sense but it is too big a breaking change I'm afraid.

Inspired by the workaround on that page, you could do something like this:

var jo = new JObject(); jo["CamelCase"] = 1;  string json = JsonConvert.SerializeObject(jo); var jObject = JsonConvert.DeserializeObject<ExpandoObject>(json);  var settings = new JsonSerializerSettings() {     ContractResolver = new CamelCasePropertyNamesContractResolver() };  var serialized = JsonConvert.SerializeObject(jObject, settings);  Assert.AreEqual("{\"camelCase\":1}", serialized); 

Edit:

Good point about the Dictionary<string, object>. So doing it this way skips the additional JsonConvert.SerializeObject, but it also mitigates the need for the ExpandoObject, which is important if you are using .NET 3.5.

Dictionary<string, object> jo = new Dictionary<string, object>(); jo.Add("CamelCase", 1);  var settings = new JsonSerializerSettings() {     ContractResolver = new CamelCasePropertyNamesContractResolver() };  var serialized = JsonConvert.SerializeObject(jo, settings);  Assert.AreEqual("{\"camelCase\":1}", serialized);