PortalNavigation.AutomaticSortingMethod property

Controls the property to use when automatically sorting navigation items owned by this site.

Namespace:  Microsoft.SharePoint.Publishing.Navigation
Assembly:  Microsoft.SharePoint.Publishing (in Microsoft.SharePoint.Publishing.dll)

public AutomaticSortingMethod AutomaticSortingMethod { get; set; }

This property is useful only when PortalNavigation.OrderingMethod is set to one of the automatic sorting options.To save changes after setting this property, call the PublishingWeb.Update method.