Returns a
Polygon instance representing the current state of the builder.
Construct a Polygon - from an enumeration of MapPoints
// Use a builderEx convenience method or use a builderEx constructor.
MapPoint pt1 = MapPointBuilderEx.CreateMapPoint(1.0, 1.0);
MapPoint pt2 = MapPointBuilderEx.CreateMapPoint(1.0, 2.0);
MapPoint pt3 = MapPointBuilderEx.CreateMapPoint(2.0, 2.0);
MapPoint pt4 = MapPointBuilderEx.CreateMapPoint(2.0, 1.0);
List<MapPoint> list = new List<MapPoint>() { pt1, pt2, pt3, pt4 };
Polygon polygon = PolygonBuilderEx.CreatePolygon(list, SpatialReferences.WGS84);
// polygon.HasZ will be false - it is determined by the HasZ flag of the points in the list
// or specifically use AttributeFlags.NoAttributes
polygon = PolygonBuilderEx.CreatePolygon(list, AttributeFlags.None);
// use AttributeFlags.None as we have 2D points
PolygonBuilderEx polygonBuilder = new PolygonBuilderEx(list, AttributeFlags.None);
polygonBuilder.SpatialReference = SpatialReferences.WGS84;
polygon = polygonBuilder.ToGeometry();
Build a donut polygon
List<Coordinate2D> outerCoordinates = new List<Coordinate2D>();
outerCoordinates.Add(new Coordinate2D(10.0, 10.0));
outerCoordinates.Add(new Coordinate2D(10.0, 20.0));
outerCoordinates.Add(new Coordinate2D(20.0, 20.0));
outerCoordinates.Add(new Coordinate2D(20.0, 10.0));
// define the inner polygon as anti-clockwise
List<Coordinate2D> innerCoordinates = new List<Coordinate2D>();
innerCoordinates.Add(new Coordinate2D(13.0, 13.0));
innerCoordinates.Add(new Coordinate2D(17.0, 13.0));
innerCoordinates.Add(new Coordinate2D(17.0, 17.0));
innerCoordinates.Add(new Coordinate2D(13.0, 17.0));
PolygonBuilderEx pbEx = new PolygonBuilderEx(outerCoordinates);
Polygon donutEx = pbEx.ToGeometry() as Polygon;
double areaEx = donutEx.Area; // area = 100
pbEx.AddPart(innerCoordinates);
donutEx = pbEx.ToGeometry() as Polygon;
areaEx = donutEx.Area; // area = 84.0
areaEx = GeometryEngine.Instance.Area(donutEx); // area = 84.0
Target Platforms: Windows 11, Windows 10
ArcGIS Pro version: 3 or higher.