ArcGIS Pro 2.7 API Reference Guide
CreateCircleGraphicElement Method (IElementFactory)
Example 

ArcGIS.Desktop.Layouts Namespace > IElementFactory Interface : CreateCircleGraphicElement Method
Layout or GroupElement
EllipticArcSegment
CIMPolygonSymbol
Creates a graphic circle element on a layout from a single elliptic arc segment geometry. This method must be called on the MCT. Use QueuedTask.Run.
Syntax

Parameters

elementContainer
Layout or GroupElement
circle
EllipticArcSegment
polygonSymbol
CIMPolygonSymbol

Return Value

Returns a GraphicElement.
Exceptions
ExceptionDescription
This method or property must be called within the lambda passed to QueuedTask.Run.
Remarks
If the element container is a Layout then the element gets added to the root level of the layout TOC at the top most position. If the element container is a GroupElement then it gets added to the group at the topmost position.
Example
//Create a circle graphic element using a simple line and fill styles.

//Construct on the worker thread
await QueuedTask.Run(() =>
{
  //Build geometry
  Coordinate2D center = new Coordinate2D(2, 4);
  EllipticArcBuilder eabCir = new EllipticArcBuilder(center, 0.5, esriArcOrientation.esriArcClockwise);
  EllipticArcSegment cir = eabCir.ToSegment();

  //Set symbolology, create and add element to layout
  CIMStroke outline = SymbolFactory.Instance.ConstructStroke(ColorFactory.Instance.BlackRGB, 2.0, SimpleLineStyle.Dash);
  CIMPolygonSymbol circleSym = SymbolFactory.Instance.ConstructPolygonSymbol(ColorFactory.Instance.RedRGB, SimpleFillStyle.Solid, outline);
  GraphicElement cirElm = LayoutElementFactory.Instance.CreateCircleGraphicElement(layout, cir, circleSym);
  cirElm.SetName("New Circle");
});
Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

IElementFactory Interface
IElementFactory Members