我想在原子操作中进行检查然后更新。我正在使用 dbcontext 来管理事务。如果记录已被另一个线程修改但没有引发异常，我希望得到一个异常。任何帮助，将不胜感激。这是我的输出：
Thread-4: Reading...
Thread-5: Reading...
Thread-5: Updating destination 1
Thread-4: Updating destination 1
Thread-4: SaveChanges
Thread-5: SaveChanges
这是我的代码片段：
public static void Main(string[] args)
{
PopulateData();
(new Thread(UpdateDestination1)).Start();
(new Thread(UpdateDestination1)).Start();
}
public static void UpdateDestination1()
{
using (var context1 = new BreakAwayContext())
{
Console.WriteLine("Thread-{0}: Reading...", Thread.CurrentThread.ManagedThreadId);
var d = context1.Destinations.FirstOrDefault();
Console.WriteLine("Thread-{0}: Updating destination {1}", Thread.CurrentThread.ManagedThreadId, d.DestinationId);
d.Name = "Thread-" + Thread.CurrentThread.ManagedThreadId;
try
{
context1.SaveChanges();
Console.WriteLine("Thread-{0}: SaveChanges", Thread.CurrentThread.ManagedThreadId);
}
catch (OptimisticConcurrencyException)
{
Console.WriteLine("OptimisticConcurrencyException!!!");
throw;
}
}
}