ArcGIS Pro 2.7 API Reference Guide
ElementSelectionChangedEvent Class
Members 

ArcGIS.Desktop.Mapping.Events Namespace : ElementSelectionChangedEvent Class
Occurs when an element selection changes on a layout or graphics layer
Object Model
ElementSelectionChangedEvent ClassSubscriptionToken ClassSubscriptionToken Class
Syntax
Remarks
ElementSelectionChangedEvent is also fired whenever a view first initializes.
Reference ElementSelectionChangedEventArgs to get a list of arguments. Element selections can change on a layout or on graphics layers. Selections only change when the view displaying the layout or graphics layer(s) has been initialized.
Inheritance Hierarchy

System.Object
   ArcGIS.Core.Events.EventBase
      ArcGIS.Core.Events.CompositePresentationEvent<TPayload>
         ArcGIS.Desktop.Mapping.Events.ElementSelectionChangedEvent

Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

ElementSelectionChangedEvent Members
ArcGIS.Desktop.Mapping.Events Namespace