Iterating ConcurrentQueue<T>

Is this a safe way of iterating ConcurrentQueu开发者_开发问答e<T>?

while (cq.GetEnumerator().MoveNext())
{
    IIndexTask task;
    if (cq.TryDequeue(out task))
        task.Execute(service);
}

Just do this instead...

IIndexTask task;
while (cq.TryDequeue(out task))
{
    task.Execute(service);
}