Adding Properties to DayPilot Calendar with Joins in EF DataSource

Question

I am creating a schedule with a DayPilot Lite control. I want to add additional information to each event but can't target properties through a join.

My datasource:

    protected IEnumerable<Schedule> GetUserSched(int userId)
    {
        var query = (from i in _context.UserScheduleMaps
                     where i.UserId == userId
                     select i.ScheduleId).ToList();

        var sched = (from i in _context.Schedules
                     join r in _context.Rooms
                     on i.RoomId equals r.RoomId
                     where query.Contains(i.ScheduleId)
                     select i).ToList();

        return sched;
    }

Adding additional properties works if I target a property from the first table but not from a joined table:

    protected void calSched1_BeforeEventRender(object sender, DayPilot.Web.Ui.Events.Calendar.BeforeEventRenderEventArgs e)
    {
        if (e.DataItem.Source != null)
        {
            // e.DataItem["Room.RoomNameOrNumber"] ?
            string location = e.DataItem["RoomId"] as string;
            e.Html = e.Text + ", room: " + location;
        }
    }

How do I target properties from joined tables?

Answer 1

The solution was to cast e.DataItem.Source as the original type. I could then access the desired properties.

protected void calSched1_BeforeEventRender(object sender, BeforeEventRenderEventArgs e)
{
    if (e.DataItem.Source != null)
    {
        Schedule sched = (Schedule)e.DataItem.Source;
        e.Html = e.Text + ", room: " + sched.Room.RoomNameOrNumber;
    }
}