LINQ to Entities初始化

Question

我目前有下面的代码，用于在sql db表中生成所有当前“骑行”的列表。然而，似乎虽然表中有数据，但我无法访问它。我是不是错过了一个初始化步骤？其他想法？

using (RamRideOpsEntities myEntities = new RamRideOpsEntities())
        {
            var adminOptions = (from a in myEntities.AdminOptions
                                select new { a.ValidDate1, a.ValidDate2 }).First();

            var allRides = (from r in myEntities.Rides
                         where (r.TimeOfCall == adminOptions.ValidDate1 ||
                                r.TimeOfCall == adminOptions.ValidDate2)
                         orderby r.TimeOfCall descending
                         select r).ToList();

            TextBox1.Text = allRides[0].Name; // <- Seems there are no existing objects as rides[0] is out of bounds
        }

Answer 1

您是否检查了adminOptions变量以确认它是否包含您希望它包含的内容？

adminOptions变量的ValidDate1和ValidDate2属性是Rides表外部的allRides查询的唯一条件，因此我猜测allRides查询可能是正常的；但是，adminOptions查询可能有问题。