/// <summary>
/// Internal method to move elements within the two internal stacks.
/// </summary>
private void MoveStack()
{
// If there are no items in the oldest item stack, move any items
// from the newest item stack.
if (StackOldestQueue.Count == 0)
{
while (StackNewestQueue.Count != 0)
{
StackOldestQueue.Push(StackNewestQueue.Pop());
}
}
}
/// <summary>
/// Gets the first item in the queue w/o removing it. If there are no items in the queue, throws an exception.
/// </summary>
/// <returns>The item.</returns>
public T Peek()
{
// Check for empty queue.
if (Count == 0)
{
throw new InvalidOperationException();
}
// Init temporary stack & copy to it.
MoveStack();
// Pop for temp stack.
return(StackOldestQueue.Peek());
}