In the past you had to configure http responses like this:

 throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.NotFound));

or

 return new HttpResponseMessage(HttpStatusCode.OK);

 

Now you can do the following:

 public IHttpActionResult GetProduct(int id)
 {
 var product = products.FirstOrDefault((p) => p.Id == id);
 if (product == null)
 {
 return NotFound();
 }
 return Ok(product);
 }

Here are a few articles about it and a working example download

Download will work in VS 2015 or 2017 – just make sure you unlock after unzipping and use package manager to restore packages in vs.

ApiController helper methods like OK)_, NotFound() and more…

Name Description
System_CAPS_protmethod BadRequest()

Creates a BadRequestResult.
System_CAPS_protmethod BadRequest(ModelStateDictionary)

Creates an InvalidModelStateResult with the specified model state.
System_CAPS_protmethod BadRequest(String)

Creates an T:System.Web.Http.Results.ErrorMessageResult (400 Bad Request) with the specified error message.
System_CAPS_protmethod Conflict()

Creates a ConflictResult (409 Conflict).
System_CAPS_protmethod Content<T>(HttpStatusCode, T)

Creates a <see cref=”T:System.Web.Http.NegotiatedContentResult`1″ /> with the specified values.
System_CAPS_protmethod Content<T>(HttpStatusCode, T, MediaTypeFormatter)

Creates a <see cref=”T:System.Web.Http.FormattedContentResult`1″ /> with the specified values.
System_CAPS_protmethod Content<T>(HttpStatusCode, T, MediaTypeFormatter, MediaTypeHeaderValue)

Creates a <see cref=”T:System.Web.Http.FormattedContentResult`1″ /> with the specified values.
System_CAPS_protmethod Content<T>(HttpStatusCode, T, MediaTypeFormatter, String)

Creates a <see cref=”T:System.Web.Http.FormattedContentResult`1″ /> with the specified values.
System_CAPS_protmethod Created<T>(String, T)

Creates a CreatedNegotiatedContentResult<T> (201 Created) with the specified values.
System_CAPS_protmethod Created<T>(Uri, T)

Creates a CreatedNegotiatedContentResult<T> (201 Created) with the specified values.
System_CAPS_protmethod CreatedAtRoute<T>(String, IDictionary<String, Object>, T)

Creates a CreatedAtRouteNegotiatedContentResult<T> (201 Created) with the specified values.
System_CAPS_protmethod CreatedAtRoute<T>(String, Object, T)

Creates a CreatedAtRouteNegotiatedContentResult<T> (201 Created) with the specified values.
System_CAPS_pubmethod Dispose()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
System_CAPS_protmethod Dispose(Boolean)

Releases the unmanaged resources that are used by the object and, optionally, releases the managed resources.
System_CAPS_pubmethod Equals(Object)

(Inherited from Object.)
System_CAPS_pubmethod ExecuteAsync(HttpControllerContext, CancellationToken)

Executes asynchronously a single HTTP operation.
System_CAPS_protmethod Finalize()

(Inherited from Object.)
System_CAPS_pubmethod GetHashCode()

(Inherited from Object.)
System_CAPS_pubmethod GetType()

(Inherited from Object.)
System_CAPS_protmethod Initialize(HttpControllerContext)

Initializes the ApiController instance with the specified controllerContext.
System_CAPS_protmethod InternalServerError()

Creates an InternalServerErrorResult (500 Internal Server Error).
System_CAPS_protmethod InternalServerError(Exception)

Creates an ExceptionResult (500 Internal Server Error) with the specified exception.
System_CAPS_protmethod Json<T>(T)

Creates a JsonResult<T> (200 OK) with the specified value.
System_CAPS_protmethod Json<T>(T, JsonSerializerSettings)

Creates a JsonResult<T> (200 OK) with the specified values.
System_CAPS_protmethod Json<T>(T, JsonSerializerSettings, Encoding)

Creates a JsonResult<T> (200 OK) with the specified values.
System_CAPS_protmethod MemberwiseClone()

(Inherited from Object.)
System_CAPS_protmethod NotFound()

Creates a NotFoundResult.
System_CAPS_protmethod Ok()

Creates an OkResult (200 OK).
System_CAPS_protmethod Ok<T>(T)

Creates an OkNegotiatedContentResult<T> with the specified values.
System_CAPS_protmethod Redirect(String)

Creates a redirect result (302 Found) with the specified value.
System_CAPS_protmethod Redirect(Uri)

Creates a redirect result (302 Found) with the specified value.
System_CAPS_protmethod RedirectToRoute(String, IDictionary<String, Object>)

Creates a redirect to route result (302 Found) with the specified values.
System_CAPS_protmethod RedirectToRoute(String, Object)

Creates a redirect to route result (302 Found) with the specified values.
System_CAPS_protmethod ResponseMessage(HttpResponseMessage)

Creates a ResponseMessageResult with the specified response.
System_CAPS_protmethod StatusCode(HttpStatusCode)

Creates a T:System.Web.Http.StatusCodeResult with the specified status code.
System_CAPS_pubmethod ToString()

(Inherited from Object.)
System_CAPS_protmethod Unauthorized(AuthenticationHeaderValue[])

Creates an UnauthorizedResult (401 Unauthorized) with the specified values.
System_CAPS_protmethod Unauthorized(IEnumerable<AuthenticationHeaderValue>)

Creates an UnauthorizedResult (401 Unauthorized) with the specified values.
System_CAPS_pubmethod Validate<TEntity>(TEntity)

Validates the given entity and adds the validation errors to the model state under the empty prefix, if any.
System_CAPS_pubmethod Validate<TEntity>(TEntity, String)

Validates the given entity and adds the validation errors to the model state, if any.