ArcGIS Pro 3.0 API Reference Guide
ArcGIS.Desktop.Editing Namespace / AnnotationProperties Class / Underline Property

Underline Property (AnnotationProperties)
Gets and sets whether to draw the annotation with an underline.
Syntax
public Nullable<bool> Underline {get; set;}
Requirements

Target Platforms: Windows 11, Windows 10, Windows 8.1

ArcGIS Pro version: 2.2 or higher.
See Also