实体框架对象上下文刷新问题

Question

我已经创建了实体框架对象来从MVC中的其他表中获取数据。但是我的上下文无法刷新，并且每次返回旧值时都无法刷新。下面是代码。

LPDBContext newdb = new LPDBContext();  
            //using (LPDBContext newdb = new LPDBContext())  
            var objectContext = ((IObjectContextAdapter)newdb).ObjectContext;  
            var MyThk = (from ot in newdb.Processes  
                         join v in newdb.PipeAls on ot.PIPENO equals v.PIPENO  
                         join c in newdb.Orders on v.OrderSYSID equals c.OrderSYSID  
                         select c.THK).FirstOrDefault().GetValueOrDefault();  

            objectContext.Refresh(RefreshMode.StoreWins, MyThk);  


            if (ModelState.IsValid)  
            {  
                //if ((MyThk >= 6 && MyThk <= 12) /*&& (MyDia >= 1 && MyDia <= 108) && (MyLength >= 5 && MyLength <= 7)*/)  
                if (MyThk>10)  
                {  
                    process.MPP = 80;  
                    process.TPCPL = 3;  
                }  
                else  
                {  
                process.MPP = 10;  
                }  

                process.CuttingSpeed = (process.ActualMeter*1000)/process.CuttingTime;  
                newdb.Processes.Add(process);  
               newdb.SaveChanges();  

                return RedirectToAction("IndexP3");  

            }