public override int AddOrUpdate(Foobaritem)
        {
            using (var ctx = new DataContext())
            {
                if (item.IsNew)
                {
                    ctx.Entry(item).State = EntityState.Added;
                }
                else
                {
                    foreach (var person in item.Persons)
                    {
                        if (person .IsNew)
                        {
                            person .FoobarID= item.ID;
                        }
                    }

                    ctx.Entry(item).State = EntityState.Modified;
                    foreach (var person in item.Persons)
                    {
                        ctx.Entry(person).State = person.IsNew ? EntityState.Added : EntityState.Modified;

                    }
                }
                return ctx.SaveChanges();
            }
        }