void HandleCheckoutElementsRequestTooLargeException(Document doc)
{
   FilteredElementCollector collector = new FilteredElementCollector(doc);
   ICollection<ElementId> rooms = collector.WherePasses(new RoomFilter()).ToElementIds();

   try
   {
      ICollection<ElementId> checkoutelements = WorksharingUtils.CheckoutElements(doc, rooms);
   }
   catch (Autodesk.Revit.Exceptions.CheckoutElementsRequestTooLargeException)
   {
      IEnumerable<WorksetId> worksets = rooms.Select(elemId => doc.GetWorksetId(elemId)).Distinct();

      TaskDialog dlg = new TaskDialog("Elements can't be checked out")
      {
         MainInstruction = $"You are trying to check out a large number of elements. Instead check out the following {worksets.Count()} worksets:",
         MainContent = string.Join(", ", worksets),
      };
      dlg.Show();

      TransactWithCentralOptions twcOptions = new TransactWithCentralOptions();
      ISet<WorksetId> worksetsCheckedout = WorksharingUtils.CheckoutWorksets(doc, worksets.ToHashSet(), twcOptions);

      TaskDialog.Show(
            title: "Worksets are checked out",
            mainInstruction: $"{worksetsCheckedout.Count} worksets are checked out.");
   }
}