Put content in HttpResponseMessage object?

Question

Several months ago, Microsoft decided to change up the HttpResponseMessage class. Before, you could simply pass a data type into the constructor, and then return the message

Answer 1

Apparently the new way to do it is detailed here:

http://aspnetwebstack.codeplex.com/discussions/350492

To quote Henrik,

HttpResponseMessage response = new HttpResponseMessage();

response.Content = new ObjectContent<T>(T, myFormatter, "application/some-format");

So basically, one has to create a ObjectContent type, which apparently can be returned as an HttpContent object.

Answer 2

You should create the response using Request.CreateResponse:

HttpResponseMessage response =  Request.CreateResponse(HttpStatusCode.BadRequest, "Error message");

You can pass objects not just strings to CreateResponse and it will serialize them based on the request's Accept header. This saves you from manually choosing a formatter.

Answer 3

No doubt that you are correct Florin. I was working on this project, and found that this piece of code:

product = await response.Content.ReadAsAsync<Product>();

Could be replaced with:

response.Content = new StringContent(string product);

Answer 4

For a string specifically, the quickest way is to use the StringContent constructor

response.Content = new StringContent("Your response text");

There are a number of additional HttpContent class descendants for other common scenarios.

Answer 5

Inspired by Simon Mattes' answer, I needed to satisfy IHttpActionResult required return type of ResponseMessageResult. Also using nashawn's JsonContent, I ended up with...

        return new System.Web.Http.Results.ResponseMessageResult(
            new System.Net.Http.HttpResponseMessage(System.Net.HttpStatusCode.OK)
            {
                Content = new JsonContent(JsonConvert.SerializeObject(contact, Formatting.Indented))
            });

See nashawn's answer for JsonContent.

Answer 6

The easiest single-line solution is to use

return new HttpResponseMessage( HttpStatusCode.OK ) {Content =  new StringContent( "Your message here" ) };

For serialized JSON content:

return new HttpResponseMessage( HttpStatusCode.OK ) {Content =  new StringContent( SerializedString, System.Text.Encoding.UTF8, "application/json" ) };