Upgrading EPiServer 8 to 9 might result in this warning:
Warning CS0618 ‘PermanentLinkMapStore.TryToMapped(string, out string)’ is obsolete: ‘This method only supports classic/mapped url’s which are no longer used since 8.0 – use PermanentLinkUtility.GetGuid(url) to get the unique ID from an URL’
How to solve warning:
You can try:
EPiServer.Web.Routing.UrlResolver.Current.GetPermanent();
or
EPiServer.Web.Routing.UrlResolver.Current.TryToPermanent();
to get a permanent link
See more info here: PermanentLinkMapStore.TryToMapped and PermanentLinkUtility.GetContentReference not working after EPiServer 9 Upgrade