LastModifiedCaching.cs

 public class MatchesController : ApiController
    {
        private static IMatchRepository _repository;

        public MatchesController(IMatchRepository repository)
        {
            _repository = repository;
        }



       
        public async Task<HttpResponseMessage> Get()
        {
            var items = await _repository.GetAsync();
            var testDate = new DateTime(2010, 03, 01);

            //todo this would be an actionfilter or message inspector??
            //i would query items on the if modified and if nothing returned, i would send back the 204
            if (Request.Headers.Contains("If-Modified-Since"))
            {
                var checkDateHeaders = Request.Headers.GetValues("If-Modified-Since");
                var date = DateTime.Parse(checkDateHeaders.FirstOrDefault());
                if (date <= testDate)
                {
                    return Request.CreateResponse(HttpStatusCode.NoContent);
                }
            }
            /**
            //jquery sample handling the 204...
             $.ajax(
                        'http://localhost/api/matches',
                        {
                            ifModified: true,
                            dataType: 'json'
                        }
                    ).done(
                        function(data, statusDesc, jqXHR) {

                            if (jqXHR.status === 204) {
                                alert('nothing changed');
                                return;
                            }

                            $('#test').empty();
                            for (var i = 0; i < data.length; i++) {
                                $('#test').append('<li><h2>' + data[i].Name + '</h2><img src="' + data[i].Original + '"/> <img src="data:image/jpeg;base64,' + data[i].Thumbnail + '" alt="Yours pic" class="pic2" /></li>');
                            }
                        });
            **/

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

            response.Content.Headers.LastModified = testDate;
            return response;
        }
    }