ArcGIS Pro 2.8 API Reference Guide
AnnotationLayer Class
Members 

ArcGIS.Desktop.Mapping Namespace : AnnotationLayer Class
Represents layer with a collection of annotation features and their visual representation and editing (when permitted).
Object Model
AnnotationLayer ClassCIMDefinitionFilter ClassLayer ClassCIMDataConnection ClassCIMBaseLayer ClassSelection ClassSpatialReference ClassTable ClassMap ClassILayerContainer InterfaceGeometry ClassEnvelope ClassRowCursor ClassSelection Class
Syntax
Remarks
AnnotationLayer is a composite layer with one level of sublayers. It does not have any group layer inside it.
Inheritance Hierarchy

System.Object
   ArcGIS.Desktop.Framework.Contracts.PropertyChangedBase
      ArcGIS.Desktop.Mapping.MapMember
         ArcGIS.Desktop.Mapping.Layer
            ArcGIS.Desktop.Mapping.BasicFeatureLayer
               ArcGIS.Desktop.Mapping.AnnotationLayer

Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

AnnotationLayer Members
ArcGIS.Desktop.Mapping Namespace