Setting content-type for Web API 2 response

Question

I'm really confused about the most appropriate way to return responses for my RESTful API that I'm building using Web API 2.

At first I made my actions return IHttpActionResult and in the method I would use return Ok() or return NotFound() etc.

Then I found there was no Forbidden() so I thought I must be doing things wrong. So now I'm making my actions return HttpResponseMessage. In my code I'm returning a response by doing the following:

HttpResponseMessage response = Request.CreateResponse();
response.StatusCode = HttpStatusCode.OK;
response.Content = new StringContent(JsonConvert.SerializeObject(responseData));
return response;

The problem is, this response now gets sent with the Content-Type "text/plain" - it needs to be sent with the Content-Type of "application/json". I can't find how I'm supposed to alter the Content-Type of the response, but even if I could it seems cumbersome to do this with every request. Is the a better way, some sort of best practice that I'm overlooking here?

Answer 1

Instead of populating it manually, you can do this

var response = Request.CreateResponse(HttpStatusCode.OK, responseData);
return response;

This, this will return content type as json.

Answer 2

You can set content negotiation for each request by modifying a collection in global.asax

Answer 3

Have you set the JsonFormatter in your global.asax? For example:

GlobalConfiguration.Configuration.EnsureInitialized();
GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.ContractResolver = new DefaultContractResolver();

Another issue which I found is that your routing prefix / route with parameters signature on your Controller cannot be match with the Url you passing in giving usually 404 code.