How to return from an IHttpActionResult method a custom variable?

Question

I am trying to get this JSON response with an Ihttpstatus header that states code 201 and keep IHttpActionResult as my method return type.

JSON I want returned:

{"CustomerID": 324}

My method:

[Route("api/createcustomer")]
[HttpPost]
[ResponseType(typeof(Customer))]
public IHttpActionResult CreateCustomer()
{
    Customer NewCustomer = CustomerRepository.Add();
    return CreatedAtRoute<Customer>("DefaultApi", new controller="customercontroller", CustomerID = NewCustomer.ID }, NewCustomer);
}

JSON returned:

"ID": 324, "Date": "2014-06-18T17:35:07.8095813-07:00",

Here are some of the returns I've tried that either gave me uri null error or have given me a response similar to the example one above.

return Created<Customer>(Request.RequestUri + NewCustomer.ID.ToString(), NewCustomer.ID.ToString());
return CreatedAtRoute<Customer>("DefaultApi", new { CustomerID = NewCustomer.ID }, NewCustomer);

With an httpresponsemessage type method this can be solved as shown below. However I want to use an IHttpActionResult:

public HttpResponseMessage CreateCustomer()
{
    Customer NewCustomer = CustomerRepository.Add();
    return Request.CreateResponse(HttpStatusCode.Created, new { CustomerID = NewCustomer.ID });
}

Answer 1

This will get you your result:

[Route("api/createcustomer")]
[HttpPost]
//[ResponseType(typeof(Customer))]
public IHttpActionResult CreateCustomer()
{
    ...
    string location = Request.RequestUri + "/" + NewCustomer.ID.ToString();
    return Created(location, new { CustomerId = NewCustomer.ID });
}

Now the ResponseType does not match. If you need this attribute you'll need to create a new return type instead of using an anonymous type.

public class CreatedCustomerResponse
{
    public int CustomerId { get; set; }
}

[Route("api/createcustomer")]
[HttpPost]
[ResponseType(typeof(CreatedCustomerResponse))]
public IHttpActionResult CreateCustomer()
{
    ...
    string location = Request.RequestUri + "/" + NewCustomer.ID.ToString();
    return Created(location, new CreatedCustomerResponse { CustomerId = NewCustomer.ID });
}

Another way to do this is to use the DataContractAttribute on your Customer class to control the serialization.

[DataContract(Name="Customer")]
public class Customer
{
    [DataMember(Name="CustomerId")]
    public int ID { get; set; }

    // DataMember omitted
    public DateTime? Date { get; set; }
}

Then just return the created model

return Created(location, NewCustomer);
// or
return CreatedAtRoute<Customer>("DefaultApi", new controller="customercontroller", CustomerID = NewCustomer.ID }, NewCustomer);