ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Core.Geometry Namespace / IGeometryEngine Interface / Area Method
The geometry of which the area will be calculated.
Example Version

Area Method (IGeometryEngine)
Gets the area of the geometry. This is a planar measurement using 2D Cartesian mathematics to compute the area.
Syntax

Parameters

geometry
The geometry of which the area will be calculated.

Return Value

The computed area in the same units as the geometry's spatial reference unit. If the geometry is empty, then zero is returned.
Exceptions
ExceptionDescription
Geometry is null.
The method is not implemented for GeometryBag.
Example
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

Determine area of a polygon
var g1 = PolygonBuilderEx.FromJson("{\"rings\": [ [ [0, 0], [10, 0], [10, 10], [0, 10] ] ] }");
double d = GeometryEngine.Instance.Area(g1);
// d = -100.0         //negative due to wrong ring orientation
d = GeometryEngine.Instance.Area(GeometryEngine.Instance.SimplifyAsFeature(g1));
// d = 100.0        // feature has been simplifed; ring orientation is correct
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also