ArcGIS Pro 3.2 API Reference Guide
ArcGIS.Core.Geometry Namespace / IGeometryEngine Interface / Relate Method
The first geometry in the relation.
The second geometry in the relation.
The DE-9IM matrix relation encoded as a string.
Example

In This Topic
    Relate Method (IGeometryEngine)
    In This Topic
    Performs custom relational operations between two geometries using a Dimensionally Extended Nine-Intersection Model, DE-9IM, formatted string.
    Syntax

    Parameters

    geometry1
    The first geometry in the relation.
    geometry2
    The second geometry in the relation.
    relateString
    The DE-9IM matrix relation encoded as a string.

    Return Value

    Returns true if the relation holds, false otherwise.
    Exceptions
    ExceptionDescription
    Either geometry1 or geometry2 or both are null.
    The method is not implemented for GeometryBag or Multipatch.
    Incompatible spatial references between the input geometries.
    Invalid relate string; the string is null.
    Spatial reference of geometry1or geometry2is an image coordinate system.
    Remarks
    The DE-9IM is a standard used to describe spatial relationships between two geometries and can be referenced at https://en.wikipedia.org/wiki/DE-9IM.

    Examples of how to use the Relate method can be found here. All of the predefined relational operations can be defined (including Intersect, Within, Contains, Crosses, Disjoint, Overlaps, Equals and Touches).

    Example
    Determine relationship between two geometries
    // set up some geometries
    
    // points
    MapPoint point0 = MapPointBuilderEx.CreateMapPoint(0, 0, SpatialReferences.WGS84);
    MapPoint point1 = MapPointBuilderEx.CreateMapPoint(1, 1, SpatialReferences.WGS84);
    MapPoint point2 = MapPointBuilderEx.CreateMapPoint(-5, 5, SpatialReferences.WGS84);
    
    // multipoint
    List<MapPoint> points = new List<MapPoint>() { point0, point1, point2 };
    Multipoint multipoint = MultipointBuilderEx.CreateMultipoint(points, SpatialReferences.WGS84);
    
    // polygon 
    List<Coordinate2D> polygonCoords = new List<Coordinate2D>()
    {
        new Coordinate2D(-10, 0),
        new Coordinate2D(0, 10),
        new Coordinate2D(10, 0),
        new Coordinate2D(-10, 0)
    };
    Polygon polygon = PolygonBuilderEx.CreatePolygon(polygonCoords, SpatialReferences.WGS84);
    
    // polylines
    Polyline polyline1 = PolylineBuilderEx.CreatePolyline(LineBuilderEx.CreateLineSegment(new Coordinate2D(-9.1, 0.1), new Coordinate2D(0, 9)), SpatialReferences.WGS84);
    Polyline polyline2 = PolylineBuilderEx.CreatePolyline(LineBuilderEx.CreateLineSegment(new Coordinate2D(-5, 5), new Coordinate2D(0, 5)), SpatialReferences.WGS84);
    Polyline polyline3 = PolylineBuilderEx.CreatePolyline(LineBuilderEx.CreateLineSegment(new Coordinate2D(2.09, -2.04), new Coordinate2D(5, 10)), SpatialReferences.WGS84);
    Polyline polyline4 = PolylineBuilderEx.CreatePolyline(LineBuilderEx.CreateLineSegment(new Coordinate2D(10, -5), new Coordinate2D(10, 5)), SpatialReferences.WGS84);
    
    List<Segment> segments = new List<Segment>()
    {
        LineBuilderEx.CreateLineSegment(new Coordinate2D(5.05, -2.87), new Coordinate2D(6.35, 1.57)),
        LineBuilderEx.CreateLineSegment(new Coordinate2D(6.35, 1.57), new Coordinate2D(4.13, 2.59)),
        LineBuilderEx.CreateLineSegment(new Coordinate2D(4.13, 2.59), new Coordinate2D(5, 5))
    };
    Polyline polyline5 = PolylineBuilderEx.CreatePolyline(segments, SpatialReferences.WGS84);
    
    segments.Add(LineBuilderEx.CreateLineSegment(new Coordinate2D(5, 5), new Coordinate2D(10, 10)));
    
    Polyline polyline6 = PolylineBuilderEx.CreatePolyline(segments, SpatialReferences.WGS84);
    Polyline polyline7 = PolylineBuilderEx.CreatePolyline(polyline5);
    Polyline polyline8 = PolylineBuilderEx.CreatePolyline(LineBuilderEx.CreateLineSegment(new Coordinate2D(5, 5), new Coordinate2D(10, 10)), SpatialReferences.WGS84);
    
    segments.Clear();
    segments.Add(LineBuilderEx.CreateLineSegment(new Coordinate2D(0.6, 3.5), new Coordinate2D(0.7, 7)));
    segments.Add(LineBuilderEx.CreateLineSegment(new Coordinate2D(0.7, 7), new Coordinate2D(3, 9)));
    
    Polyline polyline9 = PolylineBuilderEx.CreatePolyline(segments, SpatialReferences.WGS84);
    
    // now do the Related tests
    
    // Interior/Interior Intersects
    string scl = "T********";
    bool related = GeometryEngine.Instance.Relate(polygon, polyline1, scl);     // related = true
    related = GeometryEngine.Instance.Relate(point0, point1, scl);              // related = false
    related = GeometryEngine.Instance.Relate(point0, multipoint, scl);          // related = true
    related = GeometryEngine.Instance.Relate(multipoint, polygon, scl);         // related = true
    related = GeometryEngine.Instance.Relate(multipoint, polyline1, scl);       // related = false
    related = GeometryEngine.Instance.Relate(polyline2, point2, scl);           // related = false
    related = GeometryEngine.Instance.Relate(point1, polygon, scl);             // related = true
    
    // Interior/Boundary Intersects
    scl = "*T*******";
    related = GeometryEngine.Instance.Relate(polygon, polyline2, scl);          // related = true
    related = GeometryEngine.Instance.Relate(polygon, polyline3, scl);          // related = false
    related = GeometryEngine.Instance.Relate(point1, polygon, scl);             // related = false
    
    // Boundary/Boundary Interior intersects
    scl = "***T*****";
    related = GeometryEngine.Instance.Relate(polygon, polyline4, scl);          // related = true
    
    // Overlaps Dim1
    scl = "1*T***T**";
    related = GeometryEngine.Instance.Relate(polygon, polyline5, scl);          // related = true
    
    // Crosses Area/Line (LineB crosses PolygonA)
    scl = "1020F1102";
    related = GeometryEngine.Instance.Relate(polygon, polyline6, scl);          // related = false
    related = GeometryEngine.Instance.Relate(polygon, polyline9, scl);          // related = true
    
    // Boundary/Boundary Touches
    scl = "F***T****";
    related = GeometryEngine.Instance.Relate(polygon, polyline7, scl);          // related = false
    related = GeometryEngine.Instance.Relate(polygon, polyline8, scl);          // related = true
    
    Requirements

    Target Platforms: Windows 11, Windows 10

    ArcGIS Pro version: 3 or higher.
    See Also