public static void Run()
{
//ExStart: DetermineIfOneGeometryContainsAnother
var geometry1 = new Polygon();
geometry1.ExteriorRing = new LinearRing(new[]
{
new Point(0, 0),
new Point(0, 4),
new Point(4, 4),
new Point(4, 0),
new Point(0, 0),
});
geometry1.AddInteriorRing(new LinearRing(new[]
{
new Point(1, 1),
new Point(1, 3),
new Point(3, 3),
new Point(3, 1),
new Point(1, 1),
}));
var geometry2 = new Point(2, 2);
Console.WriteLine(geometry1.SpatiallyContains(geometry2)); // False
var geometry3 = new Point(0.5, 0.5);
Console.WriteLine(geometry1.SpatiallyContains(geometry3)); // True
// 'a.SpatiallyContains(b)' equals to 'b.Within(a)'
Console.WriteLine(geometry3.Within(geometry1)); // True
//ExEnd: DetermineIfOneGeometryContainsAnother
}
public static void Run()
{
//ExStart: CreatePolygonWithHole
Polygon polygon = new Polygon();
LinearRing ring = new LinearRing();
ring.AddPoint(50.02, 36.22);
ring.AddPoint(49.99, 36.26);
ring.AddPoint(49.97, 36.23);
ring.AddPoint(49.98, 36.17);
ring.AddPoint(50.02, 36.22);
LinearRing hole = new LinearRing();
hole.AddPoint(50.00, 36.22);
hole.AddPoint(49.99, 36.20);
hole.AddPoint(49.98, 36.23);
hole.AddPoint(50.00, 36.24);
hole.AddPoint(50.00, 36.22);
polygon.ExteriorRing = ring;
polygon.AddInteriorRing(hole);
//ExEnd: CreatePolygonWithHole
}
public static void ValidateOnWrite()
{
//ExStart: ValidateGeometriesOnWrite
var exteriorRing = new LinearRing();
exteriorRing.AddPoint(0, 0);
exteriorRing.AddPoint(0, 1);
exteriorRing.AddPoint(1, 1);
exteriorRing.AddPoint(1, 0);
exteriorRing.AddPoint(0, 0);
var interiorRing = new LinearRing();
interiorRing.AddPoint(0.5, 0.5);
interiorRing.AddPoint(1, 0.5);
interiorRing.AddPoint(1, 1);
interiorRing.AddPoint(0.5, 1);
interiorRing.AddPoint(0.5, 0.5);
var invalidPolygon = new Polygon();
invalidPolygon.ExteriorRing = exteriorRing;
invalidPolygon.AddInteriorRing(interiorRing);
// invalidPolygon.IsValid == false, since polygon rings share segments (have infinite number of intersection points)
GeoJsonOptions options = new GeoJsonOptions();
options.ValidateGeometriesOnWrite = false; // false is default
File.Delete(dataDir + "not_validated_data_out.shp");
using (var nonValidatingLayer = Drivers.GeoJson.CreateLayer(dataDir + "not_validated_data_out.shp", options))
{
Feature feature = nonValidatingLayer.ConstructFeature();
feature.Geometry = invalidPolygon;
// no exception is thrown, since ValidateGeometriesOnWrite == false, and GeoJson specification doesn't say that rings of polygon can't share segments.
nonValidatingLayer.Add(feature);
}
options.ValidateGeometriesOnWrite = true;
File.Delete(dataDir + "validated_data_out.shp");
using (var validatingLayer = Drivers.GeoJson.CreateLayer(dataDir + "validated_data_out.shp", options))
{
Feature feature = validatingLayer.ConstructFeature();
feature.Geometry = invalidPolygon;
try
{
validatingLayer.Add(feature); // GisException is thrown, since polygon is not valid
}
catch (GisException e)
{
Console.WriteLine(e.Message);
}
}
//ExEnd: ValidateGeometriesOnWrite
}
