c# – 事务死锁,如何设计正确？

_innerException = {“Transaction (Process ID 94) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction.”}

以下是我如何实现我的类的方法的一些例子：

public class OrderController
{

    public Order Select(long orderID)
    {
        using (var ctx = new BackEndEntities())
        {

            try
            {
                var res = from n in ctx.Orders
                                       .Include("OrderedServices.Professional")
                                       .Include("Agency")
                                       .Include("Agent")
                          where n.OrderID == orderID
                          select n;
                return res.FirstOrDefault();
            }
            catch (Exception ex)
            {
                throw ex;
            }
         }
    }

    public bool Update(Order order)
    {
        using (var ctx = new BackEndEntities())
        {
            try
            {
                order.ModificationDate = DateTime.Now;
                ctx.Orders.Attach(order);
                ctx.SaveChanges();
                return true;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }
}

和：

public class AgentController
{

    public Agent Select(long agentID)
    {
        using (var ctx = new BackEndEntities())
        {
            try
            {
                var res = from n in ctx.Agents.Include("Orders")
                          where n.AgentID == agentID
                          select n;
                return res.FirstOrDefault();
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

    }

    public bool Update(Agent agent)
    {
        using (var ctx = new BackEndEntities())
        {
            try
            {
                agent.ModificationDate = DateTime.Now;
                ctx.Agents.Attach(agent);
                ctx.ObjectStateManager.ChangeObjectState(agent,System.Data.EntityState.Modified);
                ctx.SaveChanges();
                return true;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }
}

显然,这里的代码可能会更好,但我更喜欢EF新手.但我认为我的问题是上下文的设计问题.

我记得有人在这里提到,如果我的上下文不共享,我不会遇到这些死锁问题.

这对我来说似乎并不“共享”,因为我在每个方法中使用新的BackEndEntities(),所以我必须改变什么才能使其更加健壮？

这个DAL将用于在互联网上暴露的Web服务(在coure的代码审查之后),所以我无法控制多少会受到压力,许多不同的实例可能想要更新同一个实体.

谢谢！