ArcGIS Pro 3.3 API Reference Guide
ArcGIS.Core.Geometry Namespace / PolygonBuilderEx Class / CreatePolygon Method / CreatePolygon(IEnumerable<MapPoint>,SpatialReference) Method
Points to create the polyline. Line segments are created from the coordinates of the points. The spatial references of the points are checked for compatibility.
(Optional) The SpatialReference. The default value is null. If spatialReference is null, then the spatial reference will be inherited from points which requires traversing through the enumeration of points. For improved performance, use CreatePolygon(IEnumerable<MapPoint>,AttributeFlags,SpatialReference).
Example

In This Topic
    CreatePolygon(IEnumerable<MapPoint>,SpatialReference) Method
    In This Topic
    Convenience method to create a new instance of the Polygon class.
    Syntax
    Public Overloads Shared Function CreatePolygon( _
       ByVal points As IEnumerable(Of MapPoint), _
       Optional ByVal spatialReference As SpatialReference _
    ) As Polygon

    Parameters

    points
    Points to create the polyline. Line segments are created from the coordinates of the points. The spatial references of the points are checked for compatibility.
    spatialReference
    (Optional) The SpatialReference. The default value is null. If spatialReference is null, then the spatial reference will be inherited from points which requires traversing through the enumeration of points. For improved performance, use CreatePolygon(IEnumerable<MapPoint>,AttributeFlags,SpatialReference).

    Return Value

    Exceptions
    ExceptionDescription
    Incompatible spatial references.
    points is null.
    Remarks
    The HasZ, HasM and HasID properties are inherited from points which requires traversing through the enumeration of points. For improved performance, use CreatePolygon(IEnumerable<MapPoint>,AttributeFlags,SpatialReference).
    Example
    Builder Properties
    // list of points
    List<MapPoint> points = new List<MapPoint>
    {
      MapPointBuilderEx.CreateMapPoint(0, 0, 2, 3, 1),
      MapPointBuilderEx.CreateMapPoint(1, 1, 5, 6),
      MapPointBuilderEx.CreateMapPoint(2, 1, 6),
      MapPointBuilderEx.CreateMapPoint(0, 0)
    };
    
    // will have attributes because it is created with convenience method
    Polyline polylineWithAttrs = PolylineBuilderEx.CreatePolyline(points);
    bool hasZ = polylineWithAttrs.HasZ;          // hasZ = true
    bool hasM = polylineWithAttrs.HasM;          // hasM = true
    bool hasID = polylineWithAttrs.HasID;        // hasID = true
    
    // will not have attributes because it is specified as a parameter
    Polyline polylineWithoutAttrs = 
      PolylineBuilderEx.CreatePolyline(points, AttributeFlags.None);
    hasZ = polylineWithoutAttrs.HasZ;          // hasZ = false
    hasM = polylineWithoutAttrs.HasM;          // hasM = false
    hasID = polylineWithoutAttrs.HasID;        // hasID = false
    
    // will have attributes because it is created with convenience method
    Polygon polygonWithAttrs = PolygonBuilderEx.CreatePolygon(points);
    hasZ = polygonWithAttrs.HasZ;               // hasZ = true
    hasM = polygonWithAttrs.HasM;               // hasM = true
    hasID = polygonWithAttrs.HasID;             // hasID = true
    
    // will not have attributes because it is specified as a parameter
    Polygon polygonWithoutAttrs = 
          PolygonBuilderEx.CreatePolygon(points, AttributeFlags.None);
    hasZ = polygonWithoutAttrs.HasZ;               // hasZ = false
    hasM = polygonWithoutAttrs.HasM;               // hasM = false
    hasID = polygonWithoutAttrs.HasID;             // hasID = false
    
    // will not have attributes because it is specified as a parameter
    PolylineBuilderEx polylineB = 
               new PolylineBuilderEx(points, AttributeFlags.None);
    hasZ = polylineB.HasZ;                      // hasZ = false
    hasM = polylineB.HasM;                      // hasM = false
    hasID = polylineB.HasID;                    // hasID = false
    
    // will have attributes because it is passed an attributed polyline
    polylineB = new PolylineBuilderEx(polylineWithAttrs);
    hasZ = polylineB.HasZ;                      // hasZ = true
    hasM = polylineB.HasM;                      // hasM = true
    hasID = polylineB.HasID;                    // hasID = true
    
    // will not have attributes because it is passed a non-attributed polyline
    polylineB = new PolylineBuilderEx(polylineWithoutAttrs);
    hasZ = polylineB.HasZ;                      // hasZ = false
    hasM = polylineB.HasM;                      // hasM = false
    hasID = polylineB.HasID;                    // hasID = false
    
    // will not have attributes because it is specified as a parameter
    PolygonBuilderEx polygonB = new PolygonBuilderEx(points, AttributeFlags.None);
    hasZ = polygonB.HasZ;                       // hasZ = false
    hasM = polygonB.HasM;                       // hasM = false
    hasID = polygonB.HasID;                     // hasID = false
    
    // will have attributes because it is passed an attributed polygon
    polygonB = new PolygonBuilderEx(polygonWithAttrs);
    hasZ = polygonB.HasZ;                       // hasZ = true
    hasM = polygonB.HasM;                       // hasM = true
    hasID = polygonB.HasID;                     // hasID = true
    
    // will not have attributes because it is passed a non-attributed polygon
    polygonB = new PolygonBuilderEx(polygonWithoutAttrs);
    hasZ = polygonB.HasZ;                       // hasZ = true
    hasM = polygonB.HasM;                       // hasM = true
    hasID = polygonB.HasID;                     // hasID = true
    
    Construct a Polygon - from an enumeration of MapPoints
    // Use a builderEx convenience method or use a builderEx constructor.
    
    MapPoint pt1 = MapPointBuilderEx.CreateMapPoint(1.0, 1.0);
    MapPoint pt2 = MapPointBuilderEx.CreateMapPoint(1.0, 2.0);
    MapPoint pt3 = MapPointBuilderEx.CreateMapPoint(2.0, 2.0);
    MapPoint pt4 = MapPointBuilderEx.CreateMapPoint(2.0, 1.0);
    
    List<MapPoint> list = new List<MapPoint>() { pt1, pt2, pt3, pt4 };
    
    Polygon polygon = PolygonBuilderEx.CreatePolygon(list, SpatialReferences.WGS84);
    // polygon.HasZ will be false - it is determined by the HasZ flag of the points in the list
    
    // or specifically use AttributeFlags.NoAttributes
    polygon = PolygonBuilderEx.CreatePolygon(list, AttributeFlags.None);
    
    // use AttributeFlags.None as we have 2D points
    PolygonBuilderEx polygonBuilder = new PolygonBuilderEx(list, AttributeFlags.None);
    polygonBuilder.SpatialReference = SpatialReferences.WGS84;
    polygon = polygonBuilder.ToGeometry();
    
    Create_polygon_poly
    //Create a polygon graphic with simple line and fill styles.
    
    //Construct on the worker thread
    await QueuedTask.Run(() =>
    {
      //Build geometry
      List<Coordinate2D> plyCoords = new List<Coordinate2D>();
      plyCoords.Add(new Coordinate2D(1, 7));
      plyCoords.Add(new Coordinate2D(2, 7));
      plyCoords.Add(new Coordinate2D(2, 6.7));
      plyCoords.Add(new Coordinate2D(3, 6.7));
      plyCoords.Add(new Coordinate2D(3, 6.1));
      plyCoords.Add(new Coordinate2D(1, 6.1));
      //At 2.x - Polygon poly = PolygonBuilder.CreatePolygon(plyCoords);
      Polygon poly = PolygonBuilderEx.CreatePolygon(plyCoords);
    
      //Set symbolology, create and add element to layout
      CIMStroke outline = SymbolFactory.Instance.ConstructStroke(ColorFactory.Instance.BlueRGB, 2.0, SimpleLineStyle.DashDotDot);
      CIMPolygonSymbol polySym = SymbolFactory.Instance.ConstructPolygonSymbol(ColorFactory.Instance.RedRGB, SimpleFillStyle.ForwardDiagonal, outline);
      //At 2.x - GraphicElement polyElm = LayoutElementFactory.Instance.CreatePolygonGraphicElement(layout, poly, polySym);
      //         polyElm.SetName("New Polygon"); 
      GraphicElement polyElm = ElementFactory.Instance.CreateGraphicElement(layout, poly, polySym, "New Polygon");
    });
    Create_lasso
    //Create a graphic lasso element with simple line and fill styles.
    
    //Construct on the worker thread
    await QueuedTask.Run(() =>
    {
      //Build geometry
      List<Coordinate2D> plyCoords = new List<Coordinate2D>();
      plyCoords.Add(new Coordinate2D(1, 1));
      plyCoords.Add(new Coordinate2D(1.25, 2));
      plyCoords.Add(new Coordinate2D(1.5, 1.1));
      plyCoords.Add(new Coordinate2D(1.75, 2));
      plyCoords.Add(new Coordinate2D(2, 1.1));
      plyCoords.Add(new Coordinate2D(2.25, 2));
      plyCoords.Add(new Coordinate2D(2.5, 1.1));
      plyCoords.Add(new Coordinate2D(2.75, 2));
      plyCoords.Add(new Coordinate2D(3, 1));
      //At 2.x - Polygon poly = PolygonBuilder.CreatePolygon(plyCoords);
      Polygon poly = PolygonBuilderEx.CreatePolygon(plyCoords);
    
      //Set symbolology, create and add element to layout
      CIMStroke outline = SymbolFactory.Instance.ConstructStroke(ColorFactory.Instance.BlackRGB, 2.0, SimpleLineStyle.Solid);
      CIMPolygonSymbol polySym = SymbolFactory.Instance.ConstructPolygonSymbol(ColorFactory.Instance.RedRGB, SimpleFillStyle.ForwardDiagonal, outline);
      //At 2.x - GraphicElement polyElm = LayoutElementFactory.Instance.CreatePolygonGraphicElement(layout, poly, polySym);
      //         polyElm.SetName("New Lasso"); 
      GraphicElement polyElm = ElementFactory.Instance.CreateGraphicElement(layout, poly, polySym, "New Lasso");
    });
    Create Lasso Polygon, Freehand Element
    //Must be on QueuedTask.Run(() => { ...
    
    List<Coordinate2D> plyCoords = new List<Coordinate2D>();
    plyCoords.Add(new Coordinate2D(1, 1));
    plyCoords.Add(new Coordinate2D(1.25, 2));
    plyCoords.Add(new Coordinate2D(1.5, 1.1));
    plyCoords.Add(new Coordinate2D(1.75, 2));
    plyCoords.Add(new Coordinate2D(2, 1.1));
    plyCoords.Add(new Coordinate2D(2.25, 2));
    plyCoords.Add(new Coordinate2D(2.5, 1.1));
    plyCoords.Add(new Coordinate2D(2.75, 2));
    plyCoords.Add(new Coordinate2D(3, 1));
    Polygon poly = PolygonBuilderEx.CreatePolygon(plyCoords);
    
    //Set symbolology, create and add element to layout
    CIMStroke outline = SymbolFactory.Instance.ConstructStroke(
                ColorFactory.Instance.BlackRGB, 2.0, SimpleLineStyle.Solid);
    CIMPolygonSymbol polySym = SymbolFactory.Instance.ConstructPolygonSymbol(
             ColorFactory.Instance.RedRGB, SimpleFillStyle.ForwardDiagonal, outline);
    
    ElementFactory.Instance.CreateGraphicElement(
      container, poly, polySym, "New Lasso");
    Create Polygon Element
    //Must be on QueuedTask.Run(() => { ...
    
    //Build geometry
    List<Coordinate2D> plyCoords = new List<Coordinate2D>();
    plyCoords.Add(new Coordinate2D(1, 7));
    plyCoords.Add(new Coordinate2D(2, 7));
    plyCoords.Add(new Coordinate2D(2, 6.7));
    plyCoords.Add(new Coordinate2D(3, 6.7));
    plyCoords.Add(new Coordinate2D(3, 6.1));
    plyCoords.Add(new Coordinate2D(1, 6.1));
    Polygon poly = PolygonBuilderEx.CreatePolygon(plyCoords);
    
    //Set symbolology, create and add element to layout
    CIMStroke outline = SymbolFactory.Instance.ConstructStroke(
      ColorFactory.Instance.BlueRGB, 2.0, SimpleLineStyle.DashDotDot);
    CIMPolygonSymbol polySym = SymbolFactory.Instance.ConstructPolygonSymbol(
      ColorFactory.Instance.RedRGB, SimpleFillStyle.ForwardDiagonal, outline);
    
    ElementFactory.Instance.CreateGraphicElement(
      container, poly, polySym, "New Polygon", false);
    
    Requirements

    Target Platforms: Windows 11, Windows 10

    ArcGIS Pro version: 3 or higher.
    See Also