最近一项目里使用LINQ时，我一后台线程修改数据后，前台窗体总是得不到最新的数据。无解。

查看了获取数据的数据层，是NEW的DB应该是最新的，怎么会出现这个问题呢。

百度之后说用DB.REFRESH，强制更新，结果不是不行。我开始怀疑是后台线程的问题，结果果然发现是线程只执行了一次，没有加循环，我勒个去！

1. #region 后台作废订单
2.         private void OrderUpdateThread()
3.         {
4.             System.Threading.Thread orderThread = new System.Threading.Thread(CanceledOrders);
5.             orderThread.Start();
6.         }
7.  
8.         private void CanceledOrders()
9.         {
10.             while (true)
11.             {
12.                 try
13.                 {
14.                     using (DB.DBJewelryRetailDataContext db = new DBJewelryRetailDataContext())
15.                     {
16.                         List<DB.RetailOrder> orders = db.RetailOrder.Where(f =>
17.                             f.fDate.AddMinutes(30) <= DateTime.Now &&
18.                             f.fGatheringState == Enums.GatheringState.Unreceived&&
19.                             f.fIsDelete == false
20.                             ).ToList();
21.                         DB.InOutVouch inoutVouch = null;
22.  
23.                         foreach (DB.RetailOrder retail in orders)
24.                         {
25.                             //作废订单
26.                             retail.fIsDelete = true;
27.  
28.                             //作废收款单 
29.                             DB.GatheringVouch gv = db.GatheringVouch.FirstOrDefault(f => f.fchrID == retail.fOrderID);
30.                             if (gv != null)
31.                             {
32.                                 gv.fIsDeleted = true;
33.                             }
34.  
35.                             //删除出入库单,恢复库存
36.                             inoutVouch = db.InOutVouch.FirstOrDefault(f => f.fchrBusinessID == retail.fOrderID);
37.                             db.InOutVouchDetail.DeleteAllOnSubmit(inoutVouch.InOutVouchDetail);
38.                             db.InOutVouch.DeleteOnSubmit(inoutVouch);
39.                         }
40.  
41.                         //提交
42.                         db.SubmitChanges();
43.  
44.                         //1分钟刷新一次
45.                         System.Threading.Thread.Sleep(60000);
46.                     }
47.                 }
48.                 catch(Exception)
49.                 { 
50.                 }
51.             }
52.         }
53.         #endregion