public void QueryTest()
        {
            var id       = "id";
            var point    = new Point(new GeographicPosition(30.0, 110.0));
            var feature  = new Feature(point);
            var features = new List <Feature>();

            features.Add(feature);
            var collection = new FeatureCollection(features);
            var expected   = new FeatureCollection[] { collection };

            var url     = String.Join("/", new string[] { urlPrefix, db1, "layers", id, "data" });
            var handler = new MockHttpHandler(url, "POST", (req, res, param) =>
            {
                var result     = new RestResult();
                result.Success = true;
                result.Count   = 1;
                result.Data    = JsonConvert.SerializeObject(expected);
                return(JsonConvert.SerializeObject(result));
            });

            mockServer.AddRequestHandler(handler);

            try
            {
                var db     = new MapDB(db1);
                var filter = new QueryFilter();
                var actual = db.Query(filter, 0, 10, new string[] { id });
                Assert.AreEqual(expected[0], actual[0]);
            }
            catch (Exception ex)
            {
                Assert.Fail(ex.Message);
            }
        }