ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Core.CIM Namespace / CIMGeoFeatureLayerBase Class / ScaleSymbols Property
Example Version

ScaleSymbols Property (CIMGeoFeatureLayerBase)
Gets or sets a value indicating whether to scale the symbols in this layer based on the map's reference scale.
Syntax
public bool ScaleSymbols {get; set;}
Example
Toggle "Scale layer symbols when reference scale is set"
var featureLayer = MapView.Active.Map.GetLayersAsFlattenedList().OfType<FeatureLayer>().FirstOrDefault();
ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
{
  // get the CIM layer definition
  var cimFeatureLayer = featureLayer.GetDefinition() as ArcGIS.Core.CIM.CIMFeatureLayer;
  // turn on the option to scale the symbols in this layer based in the map's reference scale
  cimFeatureLayer.ScaleSymbols = true;
});
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also