public SlideTimeoutAwaiter(int timeout, EventHandler onTimeoutCallback = null, bool whenTimeoutThrowException = true) : base()
{
if (timeout > 0)
{
block = CallbackTimer.Default.Call(timeout, timeoutCallback);
}
_onTimeoutCallback = onTimeoutCallback;
_whenTimeoutThrowException = whenTimeoutThrowException;
}
private void callbackInvoker(object state)
{
_locker.EnterUpgradeableReadLock();
//如果回调的时候的当前值不是原来传入回调时的值,则退出操作,防止出现并发
if (!_value.Equals(state))
{
_locker.ExitUpgradeableReadLock();
return;
}
_locker.EnterWriteLock();
_isValueCreated = false;
_value = default(T);
_block.Dispose();
_block = null;
_locker.ExitWriteLock();
_locker.ExitUpgradeableReadLock();
}
