GetExteriorRings Method

In This Topic

Gets all of the exterior rings in this polygon.

Syntax

Visual Basic (Declaration)
C#

Public Function GetExteriorRings( _
   Optional ByVal setSpatialReference As Boolean _
) As IList(Of Polygon)

public IList<Polygon> GetExteriorRings( 
   bool setSpatialReference
)

Parameters

setSpatialReference: (Optional) Determines if the spatial reference should be set in each of the returned polygons. If setSpatialReference is set to true, then the spatial reference in each polygon is inherited from this polygon. If setSpatialReference is set to false, then the spatial reference in each polygon is set to null. The default value is true.

Return Value

A list of polygons representing the exterior rings in this polygon.

Remarks

An exterior ring is a part that is oriented clockwise.

Example

Get the exterior rings of a polygon - polygon.GetExteriorRing

{
  static void GetExteriorRings(Polygon inputPolygon)
  {
    if (inputPolygon == null || inputPolygon.IsEmpty)
      return;

    // polygon part count
    int partCount = inputPolygon.PartCount;
    // polygon exterior ring count
    int numExtRings = inputPolygon.ExteriorRingCount;
    // get set of exterior rings for the polygon
    IList<Polygon> extRings = inputPolygon.GetExteriorRings();

    // test each part for "exterior ring"
    for (int idx = 0; idx < partCount; idx++)
    {
      bool isExteriorRing = inputPolygon.IsExteriorRing(idx);
      var ring = inputPolygon.GetExteriorRing(idx);
    }
  }
}

Requirements

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

ArcGIS Pro version: 3.0 or higher.

Reference

Polygon Class
Polygon Members

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