ArcGIS Pro 2.8 API Reference Guide
BeforeSketchCompletedEvent Class
Members 

ArcGIS.Desktop.Mapping.Events Namespace : BeforeSketchCompletedEvent Class
Occurs before a sketch is completed.
Object Model
BeforeSketchCompletedEvent ClassSubscriptionToken ClassSubscriptionToken Class
Syntax
public sealed class BeforeSketchCompletedEvent : ArcGIS.Core.Events.AsyncPresentationEvent<BeforeSketchCompletedEventArgs> 
Public NotInheritable Class BeforeSketchCompletedEvent 
   Inherits ArcGIS.Core.Events.AsyncPresentationEvent(Of BeforeSketchCompletedEventArgs)
Remarks
You can Subscribe to listen for the BeforeSketchCompletedEvent and specify a delegate that will be executed upon receiving the event. To stop listening, you can Unsubscribe.

The following are examples of tools that publish the sketch events - construction tools, Edit Vertices, Align Features, Reshape.

The BeforeSketchCompletedEvent fires when a sketch is finished but before the SketchCompletedEvent and MapTool.OnSketchCompleteAsync. This event can be used to read the current sketch geometry and update it via the BeforeSketchCompletedEventArgs.SetSketchGeometry method. If there are multiple listeners to the event, each gets the latest modified sketch geometry from the previous listener.
Inheritance Hierarchy

System.Object
   ArcGIS.Core.Events.EventBase
      ArcGIS.Core.Events.AsyncPresentationEvent<TPayload>
         ArcGIS.Desktop.Mapping.Events.BeforeSketchCompletedEvent

Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

BeforeSketchCompletedEvent Members
ArcGIS.Desktop.Mapping.Events Namespace