Constructs the geometry containing points from this geometry but not the other geometry.
[Visual Basic .NET] Public Function Difference ( _ ByVal other As IGeometry _ ) As IGeometry
[C#] public IGeometry Difference ( IGeometry other );
[C++]
HRESULT Difference(
IGeometry* other,
IGeometry** resultGeom
);
[C++]Parameters
otherother is a parameter of type IGeometry
resultGeom [out, retval]resultGeom is a parameter of type IGeometry
Product Availability
Description
Difference create a Geometry that is composed only of the region unique to the base geometry but not part of the input geometry.
Remarks
ITopologicalOperator methods must be applied on high-level geometries only. High-Level geometries are point, multipoint, polyline and polygon. To use this method with low-level geometries such as segments (Line, Circular Arc, Elliptic Arc, Bézier Curve), paths or rings, they must be wrapped into high-level geometries types.
This method does not support GeometryBags.
//The following code shows to wrap a line segment into a polyline in C#
//Assume a line (line1 as ILine) is already created
object obj = Type.Missing;
ISegmentCollection segCollection = new PolylineClass() as ISegmentCollection;
segCollection.AddSegment((ISegment)line1, ref obj, ref obj);
//Set the spatial reference on the new polyline
//The spatial reference is not transfered automatically from the segments
IGeometry geom = segCollection as IGeometry;
geom.SpatialReference = spatialRef;
//Can now be used with ITopologicalOperator methods