Can anyone point me to an approqach where I can simply draw vertices on a line and have the ability to select a vertex and return its position? I have been looking at some of the editInteractiveOverlay samples and maybe I am missing something, as I don't want to actually edit the vertices. Just draw and select. Any pointers are greatly apreciated.Thanks.
Eric
One way to do that is to use an InMemoryFeatureLayer with two features. Because, if you are just selecting a vertex and displaying, you don't need an EditInterectiveOverlay. Of the two features, one for the line itself and another one for the vertex. In the code below, I use the MapClick event to select a vertex and display its X and Y values in a message box. I hope this will help.
private void Post7115()
{
winformsMap1.MapClick += new EventHandler<MapClickWinformsMapEventArgs>(winformsMap1_MapClick);
winformsMap1.MapUnit = GeographyUnit.DecimalDegree;
winformsMap1.CurrentExtent = new RectangleShape(-97.7487, 30.274, -97.7343, 30.2658);
winformsMap1.BackgroundOverlay.BackgroundBrush = new GeoSolidBrush(GeoColor.StandardColors.LightGoldenrodYellow);
ShapeFileFeatureLayer streetLayer = new ShapeFileFeatureLayer(@"..\..\Data\austinstreets.shp");
streetLayer.ZoomLevelSet.ZoomLevel01.DefaultLineStyle = LineStyles.LocalRoad2;
streetLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;
LayerOverlay staticOverlay = new LayerOverlay();
staticOverlay.Layers.Add("StreetLayer", streetLayer);
winformsMap1.Overlays.Add(staticOverlay);
LineShape lineShape = new LineShape();
lineShape.Vertices.Add(new Vertex(-97.744, 30.2732));
lineShape.Vertices.Add(new Vertex(-97.747, 30.2693));
lineShape.Vertices.Add(new Vertex(-97.7382, 30.2698));
lineShape.Vertices.Add(new Vertex(-97.7358,30.2669));
MultipointShape multipointShape = new MultipointShape();
foreach (Vertex vertex in lineShape.Vertices)
{
multipointShape.Points.Add(new PointShape(vertex));
}
InMemoryFeatureLayer inMemoryFeatureLayer = new InMemoryFeatureLayer();
inMemoryFeatureLayer.ZoomLevelSet.ZoomLevel01.DefaultPointStyle = PointStyles.CreateSimpleCircleStyle(GeoColor.StandardColors.Red, 12);
inMemoryFeatureLayer.ZoomLevelSet.ZoomLevel01.DefaultLineStyle = LineStyles.CreateSimpleLineStyle(GeoColor.StandardColors.Green, 3, true);
inMemoryFeatureLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;
inMemoryFeatureLayer.Open();
inMemoryFeatureLayer.EditTools.BeginTransaction();
inMemoryFeatureLayer.EditTools.Add(new Feature(multipointShape));
inMemoryFeatureLayer.EditTools.Add(new Feature(lineShape));
inMemoryFeatureLayer.EditTools.CommitTransaction();
inMemoryFeatureLayer.Close();
LayerOverlay lineOverlay = new LayerOverlay();
lineOverlay.Layers.Add("Line", inMemoryFeatureLayer);
winformsMap1.Overlays.Add(lineOverlay);
winformsMap1.Refresh(lineOverlay);
}
void winformsMap1_MapClick(object sender, MapClickWinformsMapEventArgs e)
{
FeatureLayer Layer = winformsMap1.FindFeatureLayer("Line");
Layer.Open();
Collection<Feature> selectedFeatures = Layer.QueryTools.GetFeaturesNearestTo(e.WorldLocation, GeographyUnit.DecimalDegree, 2,ReturningColumnsType.NoColumns); // GetFeaturesContaining(e.WorldLocation, new string[1] { "CNTRY_NAME" });
Layer.Close();
if (selectedFeatures.Count > 0)
{
foreach (Feature feature in selectedFeatures)
{
if (feature.GetWellKnownType().ToString() == "Multipoint")
{
MultipointShape multipointShape = (MultipointShape)feature.GetShape();
PointShape pointShape = multipointShape.GetClosestPointTo(e.WorldLocation, GeographyUnit.DecimalDegree);
MessageBox.Show("X: " + Math.Round(pointShape.X,4) + " Y: " + Math.Round(pointShape.Y,4), "Vertex", MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1, (MessageBoxOptions)0);
}
}
}
}
Thanks Val, this works beatifully. Exactly the pointer I needed without having to work with an editOverlay’s control points.
Eric
