我真的不知道它为什么会一直返回null,即使值存在。我需要你的帮助 我的控制MVC 4即使数据库中存在该值,也返回null
public ActionResult DeleteConfirmed(int id)
{
User user = db.Users.Find(id);
var orders = db.Orders// 1ng co nhieu hoadon
.Where(h => h.USERID == id).ToList();
if (orders != null)//each order has detail order, find them and delete
{
foreach (Order order in orders)
{
var detailorders = db.DetailOrders
.Where(detailorder => detailorder.OrderID == order.OrderID).ToList();// Return Null here
foreach (DetailOrder o in detailorders)
db.DetailOrders.Remove(o);
db.Orders.Remove(order);
}
}
db.Users.Remove(user);
db.SaveChanges();
return RedirectToAction("Index");
}
我不知道为什么detailorders返回null,帮助我。 我的模型:
public Order()
{
this.DetailOrders = new HashSet<DetailOrder>();
}
public int OrderID { get; set; }
public Nullable<int> USERID { get; set; }
public virtual ICollection<DetailOrder> DetailOrders { get; set; }
public virtual User User { get; set; }
和我DetailOrder模型。我使用EntiyFramework 5.0.0.0
public partial class DetailOrder
{
public int OrderID { get; set; } //Primary Key
public int ProductID { get; set; }// Primary Key
public virtual Order Order { get; set; }
public virtual Product Product{ get; set; }
}
什么返回null? – 2014-12-07 07:16:09
你的问题不清楚。哪个方法返回null,表的结构和它的内容是什么......你尝试选择所有没有在哪里? – Dani 2014-12-07 07:16:23
我真的需要帮助。 – 2014-12-07 07:40:01