Buffer(IEnumerable<Geometry>,Double) Method

In This Topic

Creates buffers at the specified distance around the given geometries. Will union the results of all buffers.

Syntax

Visual Basic (Declaration)
C#

Overloads Function Buffer( _
   ByVal geometries As IEnumerable(Of Geometry), _
   ByVal distance As Double _
) As Geometry

Geometry Buffer( 
   IEnumerable<Geometry> geometries,
   double distance
)

Parameters

geometries: Specifies the input geometries.
distance: The distance (in the unit of the geometry's spatial reference) to buffer the geometries.

Return Value

The polygon that represents the buffered area.

Exceptions

Exception	Description
System.ArgumentNullException	Input geometry enumerable is null or empty.
System.NotImplementedException	The method is not implemented for GeometryBag.
System.ArgumentException	The buffer distance must be a valid floating point number.

Remarks

The returned polygon is the union of all the buffered geometries.

If the buffer distance is zero and the input geometry is a polygon or an envelope, then a polygon is created from the input geometries.

If the distance is less than or equal to zero and the input geometry is not a polygon or an envelope, then an empty polygon is created.

The spatial reference of the output geometries is the first not null or unknown spatial reference found in the list of geometries. All other geometries are projected to this spatial reference, if necessary. If no such spatial reference is found, then the unknown spatial reference is used if it is found in the list. Otherwise, the spatial reference is null.

Example

Buffer multiple MapPoints

{
  // creates a buffer around each MapPoint

  List<MapPoint> pts =
  [
    MapPointBuilderEx.CreateMapPoint(1.0, 1.0),
    MapPointBuilderEx.CreateMapPoint(1.0, 2.0),
    MapPointBuilderEx.CreateMapPoint(2.0, 2.0),
    MapPointBuilderEx.CreateMapPoint(2.0, 1.0),
  ];

  Geometry ptsBuffer = GeometryEngine.Instance.Buffer(pts, 0.25);
  Polygon bufferResult = ptsBuffer as Polygon;      // bufferResult will have 4 parts
}

Buffer many different Geometry Types

{
  List<Coordinate2D> coords =
  [
    new Coordinate2D(1, 2), new Coordinate2D(3, 4), new Coordinate2D(4, 2),
    new Coordinate2D(5, 6), new Coordinate2D(7, 8), new Coordinate2D(8, 4),
    new Coordinate2D(9, 10), new Coordinate2D(11, 12), new Coordinate2D(12, 8),
    new Coordinate2D(10, 8), new Coordinate2D(12, 12), new Coordinate2D(14, 10)
  ];

  List<Geometry> manyGeometries =
  [
    MapPointBuilderEx.CreateMapPoint(coords[9]),
    PolylineBuilderEx.CreatePolyline([coords[0], coords[1], coords[2]], SpatialReferences.WGS84),
    PolylineBuilderEx.CreatePolyline([coords[3], coords[4], coords[5]]),
    PolygonBuilderEx.CreatePolygon([coords[6], coords[7], coords[8]])
  ];

  Geometry manyGeomBuffer = GeometryEngine.Instance.Buffer(manyGeometries, 0.25);
}

Requirements

Target Platforms: Windows 11 Home, Pro, Enterprise (64 bit)

ArcGIS Pro version: 3.0 or higher.

Reference

IGeometryEngine Interface
IGeometryEngine Members
Overload List

Send feedback