队列类/ IsEmpty 方法

Question

到目前为止，这一切（至少我希望如此哈哈）是

class Queue
{

    private int front = 0; //Creates front and back int holders and an array
    private int back = -1;
    private int[] anArray;

    public Queue(int size) // constructor to get the Queue size 
    {
        anArray = new int[size];
    }

    public bool IsFull
    {
        get // gets to see if the Queue is full ( I assume I did this right, It's full if the back of the queue is equal to -1 of an array)
        {
            return back == anArray.Length - 1;
        }
    }

    public bool IsEmpty
    {
        get // It's empty if the back is -1; I think this is where I messed up, I think that when it checks to see if it's empty it also doesn't check if it's empty when I have dequeued the other numbers (or write them off). Would I make something like "Return front == anArray.Length -1;" ? That would check to see when the front (The part being written to console first) hits the end of the array?
        {
            return back == -1;
        }
    }

    public void Enqueue(int valueEnqueue)
    { // Method to Enqueue the variables into the array

        if (IsFull)
        {
            //do nothing
        }
        else
        {
            back = back + 1;
            anArray[back] = valueEnqueue;

        }
    }

    public int Dequeue()
    { // Method to dequeue the variables put in
        if (IsEmpty)
        {
            //do nothing
            return 1010101010;
        }
        else
        {
            int dequeue = anArray[front];
            front = front + 1;
            return dequeue;
        }
    }

所以我猜我的问题是什么，遵守正常的队列思维（先进先出）我如何让它停止？我不断收到索引超出范围错误。

Answer 1

你想重新发明轮子吗？

为什么不使用：system.collections.queue？

http://msdn.microsoft.com/en-us/library /system.collections.queue.aspx

如果您只是想这样做，请在 system.collections.queue 上尝试 Reflector 并查看里面有什么。

Answer 2

乍一看，我怀疑您的 Dequeue 函数出现 IndexOutOfRange 异常，该函数对 front 变量没有限制，它只是在每次调用时不断递增，最终会超过数组长度。

队列结构通常被实现为循环缓冲区。请查看此处以了解可能有助于您实施的更多详细信息。

http://en.wikipedia.org/wiki/Circular_buffer

Answer 3

您有一个有限的数组，并且期望有无限的容量。数组不是最好的容器，您应该使用其他东西来实现队列，例如列表容器。

Enqueue(item) { list.Add(item); }
Dequeue() 
{ 
  if( !IsEmpty ) 
  {
    var item = list[0];
    list.Remove(item);
    return item;
  }
  return null;
}
IsFull{ get { return false; } }
IsEmpty{ get { return list.Count == 0; }