How to Enqueue a list of items in C#?

otherList.ForEach(o => q.Enqueue(o));

You can also use this extension method:

    public static void AddRange<T>(this Queue<T> queue, IEnumerable<T> enu) {
        foreach (T obj in enu)
            queue.Enqueue(obj);
    }

    Queue<int> q = new Queue<int>();
    q.AddRange(otherList); //Work!