LINQ OrderBy in an included collection

Question

I am retrieving a list of Tickets and TicketActivities via the .Include(ta => ta.TicketActivities) which is a reverse navigation property of type ICollection<TicketActivity>() on my Ticket class.

How can I sort by my tickets by the SubmitDate property and the TicketActivities by the DateTime property?

 using (var entityContext = new InformationSystemsContext())
 {
     IQueryable<Ticket> tickets = null;
     tickets = entityContext.Tickets.Include(i => i.TicketActivities)
                                    .OrderBy(t => t.SubmitDate).ThenBy(t => t.TicketActivities.DateTime);
 }

Answer 1

var query = (from Ticket in entityContext.Tickets
            join Activity in entityContext.TicketActivities
                on Ticket.ID equals Activity.TicketID into JoinedList // fields you made relationship base on those
            group JoinedList by Ticket into GroupedList
            select new {
                Ticket = GroupedList.Key,
                Activities = GroupedList.OrderBy(u => u.DateTime)
            })
            .OrderBy(u => u.SubmitDate)
            .ToList();