ExportToJson Method (GeometryEngine)

In This Topic

Writes a JSON version of the input geometry to a string.

Syntax

C#
Visual Basic (Declaration)

public string ExportToJson( 
   JsonExportFlags exportFlags,
   Geometry geometry
)

Public Function ExportToJson( _
   ByVal exportFlags As JsonExportFlags, _
   ByVal geometry As Geometry _
) As String

Parameters

exportFlags: A combination of JsonExportFlags which determines how the geometry is exported.
geometry: The input geometry to write to a string.

Return Value

The JSON version of the input geometry.

Exceptions

Exception	Description
System.ArgumentNullException	Geometry is null or empty.
System.NotImplementedException	The method is not implemented for GeometryBag.

Remarks

Note that if the contains ID information, this property will not be preserved in the JSON string. ID is not part of the JSON specification.

Example

Import and Export Geometries to JSON

// MapPoint
string inputString = 
  "{\"x\":1,\"y\":2,\"spatialReference\":{\"wkid\":4326,\"latestWkid\":4326}}";
Geometry geometry = GeometryEngine.Instance.ImportFromJson(
  JsonImportFlags.JsonImportDefaults, inputString);

MapPoint importPoint = geometry as MapPoint;
// importPoint = 1, 2
// importPoint.SpatialReference.WKid = 4326

// use the MapPointBuilderEx convenience method
MapPoint importPoint2 = MapPointBuilderEx.FromJson(inputString);
// importPoint2 = 1, 2
// impointPoint2.SpatialReference.Wkid = 4326

string outputString = GeometryEngine.Instance.ExportToJson(
  JsonExportFlags.JsonExportDefaults, importPoint);
// outputString =
//   "{\"x\":1,\"y\":2,\"spatialReference\":{\"wkid\":4326,\"latestWkid\":4326}}"

string outputString2 = importPoint.ToJson();

inputString = 
  "{\"spatialReference\":{\"wkid\":4326},\"z\":3,\"m\":4,\"x\":1,\"y\":2}";
importPoint = GeometryEngine.Instance.ImportFromJson(
  JsonImportFlags.JsonImportDefaults, inputString) as MapPoint;
// importPoint.HasM = true
// importPoint.HasZ = true
// importPoint.X = 1
// importPoint.Y = 2
// importPoint.M = 4
// importPoint.Z = 3

importPoint2 = MapPointBuilderEx.FromJson(inputString);

// export to json - skip spatial reference
outputString = GeometryEngine.Instance.ExportToJson(
              JsonExportFlags.JsonExportSkipCRS, importPoint);
// outputString = "{\"x\":1,\"y\":2,\"z\":3,\"m\":4}"

// export from mappoint, skipping the sr - same as GeometryEngine.Instance.ExportToJson w JsonExportFlags.JsonExportSkipCRS
outputString2 = importPoint.ToJson(true);

//
// Multipoint
//
List<Coordinate2D> coords = new List<Coordinate2D>()
{
  new Coordinate2D(100, 200),
  new Coordinate2D(201, 300),
  new Coordinate2D(301, 400),
  new Coordinate2D(401, 500)
};

Multipoint multipoint = MultipointBuilderEx.CreateMultipoint(
  coords, SpatialReferences.WebMercator);

inputString = 
  "{\"points\":[[100,200],[201,300],[301,400],[401,500]],\"spatialReference\":{\"wkid\":3857}}";
Multipoint importMultipoint = 
  GeometryEngine.Instance.ImportFromJson(
         JsonImportFlags.JsonImportDefaults, inputString) as Multipoint;
// importMultipoint.IsEqual(multipoint) = true

ReadOnlyPointCollection points = importMultipoint.Points;
// points.Count = 4
// points[0] = 100, 200
// points[1] = 201, 300
// points[2] = 301, 400
// points[3] = 401, 500

// use the MultipointbuilderEx convenience method
Multipoint importMultipoint2 = MultipointBuilderEx.FromJson(inputString);
// importMultipoint2.IsEqual(multipoint) = true

// export to json
outputString = GeometryEngine.Instance.ExportToJson(
                JsonExportFlags.JsonExportDefaults, multipoint);
// outputString = inputString

// or use the multipoint itself
outputString2 = multipoint.ToJson();

//
// Polyline
//
Polyline polyline = PolylineBuilderEx.CreatePolyline(
                         coords, SpatialReferences.WebMercator);

// export without the spatial reference
outputString = GeometryEngine.Instance.ExportToJson(
                        JsonExportFlags.JsonExportSkipCRS, polyline);
// import
geometry = GeometryEngine.Instance.ImportFromJson(
             JsonImportFlags.JsonImportDefaults, outputString);
Polyline importPolyline = geometry as Polyline;
// importPolyline.SpatialReference = null


points = importPolyline.Points;
// points.Count = 4
// points[0] = 100, 200
// points[1] = 201, 300
// points[2] = 301, 400
// points[3] = 401, 500

// use the polylineBuilderEx convenience method 
Polyline importPolyline2 = PolylineBuilderEx.FromJson(outputString);
// importPolyline2 = importPolyline

outputString2 = importPolyline2.ToJson();
// outputString2 = outputString

//
// Polygon
//
Polygon polygon = PolygonBuilderEx.CreatePolygon(
                              coords, SpatialReferences.WebMercator);

// export without the spatial reference
outputString = GeometryEngine.Instance.ExportToJson(
                          JsonExportFlags.JsonExportSkipCRS, polygon);
// import
geometry = GeometryEngine.Instance.ImportFromJson(
                     JsonImportFlags.JsonImportDefaults, outputString);

Polygon importPolygon = geometry as Polygon;
// importPolygon.SpatialReference = null
points = importPolygon.Points;
// points.Count = 5

// polygonBuilderEx convenience method
Polygon importPolyon2 = PolygonBuilderEx.FromJson(outputString);
// importPolygon2 = importPolygon

// export from the polygon
outputString2 = importPolyon2.ToJson(true);

// Empty polygon
polygon = PolygonBuilderEx.CreatePolygon(SpatialReferences.WebMercator);
outputString = GeometryEngine.Instance.ExportToJson(
                               JsonExportFlags.JsonExportDefaults, polygon);
importPolygon = GeometryEngine.Instance.ImportFromJson(
                    JsonImportFlags.JsonImportDefaults, outputString) as Polygon;

// importPolygon.IsEmpty = true
// importPolygon.SpatialReference.Wkid = 3857

Requirements

Target Platforms: Windows 11, Windows 10, Windows 8.1

Reference

GeometryEngine Class
GeometryEngine Members

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