ArcGIS Pro 2.8 API Reference Guide
ArcGISPortalManager Class
Members 

ArcGIS.Desktop.Core Namespace : ArcGISPortalManager Class
Manages the collection of portals currently defined for Pro. Portals can be added to and removed from the ArcGISPortalManager. The list of portals is shown on the Portals backstage tab.
Object Model
ArcGISPortalManager ClassArcGISPortal ClassArcGISPortalManager ClassArcGISPortal ClassArcGISPortal ClassArcGISPortal Class
Syntax
public class ArcGISPortalManager 
Public Class ArcGISPortalManager 
Remarks
ArcGISPortalManager is a singleton. It is accessed via its Current property.
Out of the box you will always have a portal entry defined for arcgis.com (ArcGIS Online). This portal entry cannot be deleted.
Inheritance Hierarchy

System.Object
   ArcGIS.Desktop.Core.ArcGISPortalManager

Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

ArcGISPortalManager Members
ArcGIS.Desktop.Core Namespace