ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Desktop.Mapping Namespace / Map Class / GetDefaultExtent Method
Example Version

GetDefaultExtent Method
Returns the default full extent of the map. This method must be called on the MCT. Use QueuedTask.Run.
Syntax
public Envelope GetDefaultExtent()

Return Value

An ArcGIS.Core.Internal.CIM.Envelope representing the default extent
Exceptions
ExceptionDescription
This method or property must be called within the lambda passed to QueuedTask.Run.
Example
Calculate Selection tolerance in map units
//Selection tolerance for the map in pixels
var selectionTolerance = SelectionEnvironment.SelectionTolerance;
QueuedTask.Run(() =>
{
  //Get the map center
  var mapExtent = MapView.Active.Map.GetDefaultExtent();
  var mapPoint = mapExtent.Center;
  //Map center as screen point
  var screenPoint = MapView.Active.MapToScreen(mapPoint);
  //Add selection tolerance pixels to get a "radius".
  var radiusScreenPoint = new System.Windows.Point((screenPoint.X + selectionTolerance), screenPoint.Y);
  var radiusMapPoint = MapView.Active.ScreenToMap(radiusScreenPoint);
  //Calculate the selection tolerance distance in map uints.
  var searchRadius = GeometryEngine.Instance.Distance(mapPoint, radiusMapPoint);
});
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also