var cimMapDefinition = MapView.Active.Map.GetDefinition();
// use if map's sr does not have a vertical coordinate system
var datumTransformations = cimMapDefinition.DatumTransforms;
// use if map's sr has a vertical coordinate system
var hvDatumTransformations = cimMapDefinition.HVDatumTransforms;
Requirements
Target Platforms: Windows 11, Windows 10, Windows 8.1