Question

I have a gridview, the datasource of which is the following function:

public static List<Train> GetTrainsByIDs(int [] ids) {
    using (var context = new MyEntities()) 
    {
        return ids.Select(x => context.Trains.Single(y => y.TrainID ==x)).AsQueryable().Include(x=>x.Station).ToList();
    }
}

The grid view has an ItemTemplate of <%# Eval("Station.Name") %>.
This causes the error The ObjectContext instance has been disposed and can no longer be used for operations that require a connection despite the fact that I used the include method.

When I change the function to

public static List<Train> GetTrainsByIDs(int [] ids) {
    using (var context = new MyEntities()) 
    {
        return context.Trains.Where(x => ids.Contains(x.TrainID)).Include(x=>x.Station).ToList();
    }
}

it works fine, but then they come out in the wrong order, and also if I have 2 ids the same I would like 2 identical trains in the list.

Is there anything I can do other than create a new viewmodel? Thank you for any help

Answer 1

After reading @Gert Arnold’s answer, and getting the idea of doing it in 2 stages, I managed very simply using the first query like this:

using (context = new MyEntities())
{
    var trns = context.Trains.Include(x => x.Station);
    return ids.Select(x => trns.Single(y => y.TrainID == x)).ToList();
}