ArcGIS.Desktop.Core.Events.ActivePortalChangedEvent.Subscribe((args) =>
{
var active_uri = args.ActivePortal?.PortalUri.ToString();
//etc
});
ArcGIS.Desktop.Core.Events.ArcGISPortalAddedEvent.Subscribe((args) =>
{
var added_portal = args.Portal;
//etc
});
ArcGIS.Desktop.Core.Events.ArcGISPortalRemovedEvent.Subscribe((args) =>
{
var old_uri = args.RemovedPortalUri;
//etc
});
ArcGIS.Desktop.Core.Events.PortalSignOnChangedEvent.Subscribe((args) =>
{
var portal = args.Portal;
var isSignedOn = args.IsSignedOn;
//etc
});