ShapePreservingLength Method

Calculates the length of the geometry on the surface of the Earth ellipsoid. This method preserves the shape of the geometry in its coordinate system.

Syntax

C#
Visual Basic (Declaration)

double ShapePreservingLength( 
   Geometry geometry
)

Function ShapePreservingLength( _
   ByVal geometry As Geometry _
) As Double

Parameters

geometry: The input geometry.

Return Value

Length of the geometry in meters. If the geometry is empty, then zero is returned.

Exceptions

Exception	Description
System.ArgumentNullException	Geometry is null.
System.NotImplementedException	The method is not implemented for GeometryBag or Multipatch.
ProjectionEngineException	Geometry is missing a spatial reference.
System.NotImplementedException	Spatial reference of geometryis an image coordinate system.

Remarks

This method preserves the shape of the geometry in its coordinate system. In other words, the length will be calculated for the geometry you see in the map. For example, if you have a polyline with only two vertices that represents the equator, the length returned will be the length of the equator.

Example

// pt
MapPoint pt = MapPointBuilder.CreateMapPoint(1.0, 3.0, SpatialReferences.WebMercator);
double len = GeometryEngine.Instance.ShapePreservingLength(pt);          // len = 0

List<MapPoint> pts = new List<MapPoint>();
pts.Add(MapPointBuilder.CreateMapPoint(1.0, 1.0, 3.0));
pts.Add(MapPointBuilder.CreateMapPoint(1.0, 3.0, 3.0));
pts.Add(MapPointBuilder.CreateMapPoint(3, 3, 3.0));
pts.Add(MapPointBuilder.CreateMapPoint(3.0, 1.0, 3.0));

// multipoint
Multipoint mPt = MultipointBuilder.CreateMultipoint(pts);
len = GeometryEngine.Instance.ShapePreservingLength(mPt);                // len = 0

// polyline
Polyline polyline = PolylineBuilder.CreatePolyline(pts, SpatialReferences.WGS84);
len = GeometryEngine.Instance.ShapePreservingLength(polyline);

// polygon
Polygon polygon = PolygonBuilder.CreatePolygon(pts, SpatialReferences.WGS84);
len = GeometryEngine.Instance.ShapePreservingLength(polygon);

Requirements

Target Platforms: Windows 10, Windows 8.1

Reference

IGeometryEngine Interface
IGeometryEngine Members