agrobot_base/Exemplos/Aspose.GIS-for-.NET-master/Examples/CSharp/Geometries/GeometryValidation.cs

136 lines
5.0 KiB
C#

using Aspose.Gis;
using Aspose.Gis.Formats.GeoJson;
using Aspose.Gis.Geometries;
using Aspose.GIS.Examples.CSharp;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Aspose.GIS_for.NET.Geometries
{
public class GeometryValidation
{
static string dataDir = RunExamples.GetDataDir();
public static void Run()
{
IsGeometryValid();
IsGeometrySimple();
ValidateOnWrite();
ValidateOnWriteObeyingSpecifications();
}
public static void IsGeometryValid()
{
//ExStart: IsGeometryValid
LinearRing linearRing = new LinearRing();
linearRing.AddPoint(0, 0);
linearRing.AddPoint(0, 1);
linearRing.AddPoint(1, 0);
bool valid = linearRing.IsValid; // valid == false
linearRing.AddPoint(0, 0);
valid = linearRing.IsValid; // valid == true
//ExEnd: IsGeometryValid
}
public static void IsGeometrySimple()
{
//ExStart: IsGeometrySimple
LineString lineString = new LineString();
bool simple = lineString.IsSimple; // simple == true
lineString.AddPoint(0, 0);
lineString.AddPoint(1, 0);
simple = lineString.IsSimple; // simple == true
lineString.AddPoint(0.5, 0);
simple = lineString.IsSimple; // simple == false (line string crosses itself)
//ExEnd: IsGeometrySimple
}
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
}
public static void ValidateOnWriteObeyingSpecifications()
{
//ExStart: ValidateOnWriteObeyingSpecifications
LineString lineStrinWithOnePoint = new LineString();
lineStrinWithOnePoint.AddPoint(0, 0);
GeoJsonOptions options = new GeoJsonOptions();
options.ValidateGeometriesOnWrite = false;
using (var layer = Drivers.GeoJson.CreateLayer(dataDir + "ValidateOnWriteObeyingSpecifications_out.json", options))
{
Feature feature = layer.ConstructFeature();
// GeoJSON specification says that line string must have at least two coordinates.
feature.Geometry = lineStrinWithOnePoint;
try
{
// Geometry of feature doesn't match data format specification, so exception is thrown
// regardless what ValidateGeometriesOnWrite option is.
layer.Add(feature);
}
catch (GisException e)
{
Console.WriteLine(e.Message);
}
}
//ExEnd: ValidateOnWriteObeyingSpecifications
}
}
}