אימות גיאומטריה

ממשק ה-API של Aspose.GIS מאפשר לך לאמת גיאומטריות למספר פעולות. הוא מספק לך את היכולת לאמת גיאומטריה עבור כללים הקשורים לגיאומטריות, כמו גם מפרטים על ידי פורמטי קבצים גיאוגרפיים.

בדיקת גיאומטריה לתקינות

// For complete examples and data files, please go to https://github.com/aspose-gis/Aspose.GIS-for-.NET
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

בדיקת גיאומטריה לפשטות

// For complete examples and data files, please go to https://github.com/aspose-gis/Aspose.GIS-for-.NET
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)

אימות גיאומטריות בכתיבה

// For complete examples and data files, please go to https://github.com/aspose-gis/Aspose.GIS-for-.NET
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);
    }
}

אימות גיאומטריות בכתיבה תוך שמירה על מפרטים

// For complete examples and data files, please go to https://github.com/aspose-gis/Aspose.GIS-for-.NET
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);
    }
}