ArcGIS Pro 3.0 API Reference Guide
ArcGIS.Desktop.Framework Namespace / PaneCollection Class / Count Property

Count Property (PaneCollection)
Gets the number of currently open panes.
Syntax
public int Count {get;}
Requirements

Target Platforms: Windows 11, Windows 10, Windows 8.1

ArcGIS Pro version: 2.0 or higher.
See Also