ArcGIS Pro 2.8 API Reference Guide
SubtypeGroupLayer Class
Members 

ArcGIS.Desktop.Mapping Namespace : SubtypeGroupLayer Class
Represents a composite layer with a collection of feature layers for each ArcGIS.Core.Data.Subtype of its source ArcGIS.Core.Data.FeatureClass and their visual representation and editing (when permitted).
Object Model
SubtypeGroupLayer ClassCIMDefinitionFilter ClassLayer ClassCIMDataConnection ClassCIMBaseLayer ClassSpatialReference ClassMap ClassILayerContainer InterfaceEnvelope Class
Syntax
Remarks
To create a SubtypeGroupLayer, you must call LayerFactory.CreateLayer<T> and pass in a SubtypeGroupLayerCreationParams, instead of directly using a constructor.
Inheritance Hierarchy

System.Object
   ArcGIS.Desktop.Framework.Contracts.PropertyChangedBase
      ArcGIS.Desktop.Mapping.MapMember
         ArcGIS.Desktop.Mapping.Layer
            ArcGIS.Desktop.Mapping.CompositeLayer
               ArcGIS.Desktop.Mapping.SubtypeGroupLayer

Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

SubtypeGroupLayer Members
ArcGIS.Desktop.Mapping Namespace