ArcGIS Pro 3.3 API Reference Guide
ArcGIS.Core.Geometry Namespace / Multipart Class / Parts Property
Example

In This Topic
    Parts Property (Multipart)
    In This Topic
    Gets the parts in this instance.
    Syntax
    public virtual ReadOnlyPartCollection Parts {get;}
    Public Overridable ReadOnly Property Parts As ReadOnlyPartCollection
    Example
    Get the parts of a Polyline
    int numParts = polyline.PartCount;
    // get the parts as a readonly collection
    ReadOnlyPartCollection parts = polyline.Parts;
    
    Enumerate the parts of a Polyline
    ReadOnlyPartCollection polylineParts = polyline.Parts;
    
    // enumerate the segments to get the length
    double len = 0;
    IEnumerator<ReadOnlySegmentCollection> segments = polylineParts.GetEnumerator();
    while (segments.MoveNext())
    {
      ReadOnlySegmentCollection seg = segments.Current;
      foreach (Segment s in seg)
      {
        len += s.Length;
    
        // perhaps do something specific per segment type
        switch (s.SegmentType)
        {
          case SegmentType.Line:
            break;
          case SegmentType.Bezier:
            break;
          case SegmentType.EllipticArc:
            break;
        }
      }
    }
    
    // or use foreach pattern
    foreach (var part in polyline.Parts)
    {
      foreach (var segment in part)
      {
        len += segment.Length;
    
        // perhaps do something specific per segment type
        switch (segment.SegmentType)
        {
          case SegmentType.Line:
            break;
          case SegmentType.Bezier:
            break;
          case SegmentType.EllipticArc:
            break;
        }
      }
    }
    StartPoint of a Polyline
    // Method 1: Get the start point of the polyline by converting the polyline 
    //    into a collection of points and getting the first point
    
    // sketchGeometry is a Polyline
    // get the sketch as a point collection
    var pointCol = ((Multipart)sketchGeometry).Points;
    // Get the start point of the line
    var firstPoint = pointCol[0];
    
    // Method 2: Convert polyline into a collection of line segments 
    //   and get the "StartPoint" of the first line segment.
    var polylineGeom = sketchGeometry as ArcGIS.Core.Geometry.Polyline;
    var polyLineParts = polylineGeom.Parts;
    
    ReadOnlySegmentCollection polylineSegments = polyLineParts.First();
    
    //get the first segment as a LineSegment
    var firsLineSegment = polylineSegments.First() as LineSegment;
    
    //Now get the start Point
    var startPoint = firsLineSegment.StartPoint;
    
    Get the parts of a Polygon
    // get the parts as a readonly collection
    ReadOnlyPartCollection parts = polygon.Parts;
    
    Enumerate the parts of a Polygon
    int numSegments = 0;
    IEnumerator<ReadOnlySegmentCollection> segments = polygon.Parts.GetEnumerator();
    while (segments.MoveNext())
    {
      ReadOnlySegmentCollection seg = segments.Current;
      numSegments += seg.Count;
      foreach (Segment s in seg)
      {
        // do something with the segment
      }
    }
    
    Get the individual parts of a multipart feature
    /// <summary>
    /// This method takes an input multi part geometry and breaks the parts into individual standalone geometries.
    /// </summary>
    /// <param name="inputGeometry">The geometry to be exploded into the individual parts.</param>
    /// <returns>An enumeration of individual parts as standalone geometries. The type of geometry is maintained, i.e.
    /// if the input geometry is of type Polyline then each geometry in the return is of type Polyline as well.
    /// If the input geometry is of type Unknown then an empty list is returned.</returns>
    public IEnumerable<Geometry> MultipartToSinglePart(Geometry inputGeometry)
    {
      // list holding the part(s) of the input geometry
      List<Geometry> singleParts = new List<Geometry>();
    
      // check if the input is a null pointer or if the geometry is empty
      if (inputGeometry == null || inputGeometry.IsEmpty)
        return singleParts;
    
      // based on the type of geometry, take the parts/points and add them individually into a list
      switch (inputGeometry.GeometryType)
      {
        case GeometryType.Envelope:
          singleParts.Add(inputGeometry.Clone() as Envelope);
          break;
        case GeometryType.Multipatch:
          singleParts.Add(inputGeometry.Clone() as Multipatch);
          break;
        case GeometryType.Multipoint:
          var multiPoint = inputGeometry as Multipoint;
    
          foreach (var point in multiPoint.Points)
          {
            // add each point of collection as a standalone point into the list
            singleParts.Add(point);
          }
          break;
        case GeometryType.Point:
          singleParts.Add(inputGeometry.Clone() as MapPoint);
          break;
        case GeometryType.Polygon:
          var polygon = inputGeometry as Polygon;
    
          foreach (var polygonPart in polygon.Parts)
          {
            // use the PolygonBuilderEx turning the segments into a standalone 
            // polygon instance
            singleParts.Add(PolygonBuilderEx.CreatePolygon(polygonPart));
          }
          break;
        case GeometryType.Polyline:
          var polyline = inputGeometry as Polyline;
    
          foreach (var polylinePart in polyline.Parts)
          {
            // use the PolylineBuilderEx turning the segments into a standalone
            // polyline instance
            singleParts.Add(PolylineBuilderEx.CreatePolyline(polylinePart));
          }
          break;
        case GeometryType.Unknown:
          break;
        default:
          break;
      }
    
      return singleParts;
    }
    
    Requirements

    Target Platforms: Windows 11, Windows 10

    ArcGIS Pro version: 3 or higher.
    See Also