private void btnRoute_Click(object sender, EventArgs e) { ShapeFileFeatureSource featureSource = new ShapeFileFeatureSource(@"..\..\SampleData\Austinstreets.shp"); RoutingSource routingSource = new RtgRoutingSource(@"..\..\SampleData\routeDataForFastest.rtg"); RoutingEngine routingEngine = new RoutingEngine(routingSource, featureSource); RoutingResult routingResult = routingEngine.GetShortestPath(txtStartId.Text, txtEndId.Text); InMemoryFeatureLayer routingLayer = (InMemoryFeatureLayer)((LayerOverlay)winformsMap1.Overlays["RoutingOverlay"]).Layers["RoutingLayer"]; winformsMap1.Overlays["RoutingOverlay"].Lock.EnterWriteLock(); try { routingLayer.InternalFeatures.Clear(); foreach (Feature feature in routingResult.Features) { routingLayer.InternalFeatures.Add(feature); } } finally { winformsMap1.Overlays["RoutingOverlay"].Lock.ExitWriteLock(); } winformsMap1.Refresh(); }