ArcGIS Pro 3.0 API Reference Guide
ArcGIS.Core.CIM Namespace / CIMDimensionStyle Class / ExtensionLineSymbol Property

ExtensionLineSymbol Property
Gets or sets the symbol used for extension lines.
Syntax
public CIMLineSymbol ExtensionLineSymbol {get; set;}
Requirements

Target Platforms: Windows 11, Windows 10, Windows 8.1

ArcGIS Pro version: 2.0 or higher.
See Also