private bool HasExpiredTimer(Guid workflowInstanceId, out Guid timerId) { lock (locker) { CallbackInfo ci = pendingScheduleRequests.FindByPriority(DateTime.UtcNow, delegate(CallbackInfo c) { return(c.InstanceId == workflowInstanceId); }); if (ci != null) { timerId = ci.TimerId; return(true); } } timerId = Guid.Empty; return(false); }