C# 实现队列

C#实现队列，能实现循环队列，缺点是可用长度比声明的长度少1。

代码：

 

    /// <summary>
    /// 队列
    /// </summary>
    public class Queue
    {
        private object[] data; //用数组data来存储数据
        protected int length;
        protected int head;    //头指针
        protected int tail;    //尾指针

        public int Length
        {
            get { return this.length; }  //可读不可写
        }

        public object this[int index]
        {
            get { return this.data[index]; }
        }

        public Queue(int size)
        {
            data = new object[size];
            length = size;
            head = 0;              //头指针赋0
            tail = 0;              //尾指针赋0
        }

        /// <summary>
        /// Queue 是否空
        /// </summary>
        /// <returns></returns>
        public bool isEmpty()
        {
            return head == tail;
        }

        /// <summary>
        /// Queue 是否满
        /// </summary>
        /// <returns></returns>
        public bool isFull()
        {
            return this.length == 0 || (this.tail + 1) % this.length == this.head;
        }

        /// <summary>
        /// 进队列
        /// </summary>
        /// <param name="elem"></param>
        public void Push(object elem)
        {
            if (this.isFull())
            {
                throw new Exception("Queue is already full!");
            }
            this.data[this.tail] = elem;
            tail = (tail + 1) % this.length;
        }

        /// <summary>
        /// 出队列
        /// </summary>
        /// <returns></returns>
        public object Pull()
        {
            if (this.isEmpty())
            {
                throw new Exception("Queue is empty!");
            }
            object element =this.data[this.head];
            head = (this.head + 1) % this.length;
            return element;
        }

        /// <summary>
        /// 获取头元素
        /// </summary>
        /// <returns></returns>
        public object getHeadElement()
        {
            if (this.isEmpty())
            {
                throw new Exception("Queue is empty!");
            }
            return this.data[head];
        }

        /// <summary>
        /// 获取尾元素
        /// </summary>
        /// <returns></returns>
        public object getTailElement()
        {
            if (this.isEmpty())
            {
                throw new Exception("Queue is empty!");
            }
            int loc = this.tail == 0 ? this.length - 1 : (this.tail - 1) % this.length;
            return this.data[loc];
        }

        /// <summary>
        /// 清空队列
        /// </summary>
        public void Clear()
        {
            this.head = this.tail = 0;
        }
    }