之前寫Web沒有應用到多線程與隊列的知識，寫了個小程序，練了一把手，模擬商品搶購，代碼如下：

 class Program
    {
        public static Random r = new Random();
        public static int GoodsStock = 30;
        public static Queue payq = new Queue();
        public static Queue waitq = new Queue();

        static void Main(string[] args)
        {
            
 
//增加監視線程
            ThreadStart childref3 = new ThreadStart(LookAtActiveThread);
            Console.WriteLine("監視線程啟動了！");
            Thread childThread3 = new Thread(childref3);
            childThread3.Start();
            //增加用戶搶購線程
            ThreadStart childref1 = new ThreadStart(UserBuyInsertThread);
            Console.WriteLine(
 
"用戶群1開始搶購了！");
            Thread childThread1 = new Thread(childref1);
            childThread1.Start();
            //增加用戶搶購線程
            ThreadStart childref4 = new ThreadStart(UserBuyInsertThread);
            Console.WriteLine("用戶群2開始搶購了！");
            Thread childThread4 = new Thread(childref4);
            childThread4.Start();
            
 
//增加開始結賬線程
            ThreadStart childref2 = new ThreadStart(UserPayEndThread);
            Console.WriteLine("結賬線程啟動了！");
            Thread childThread2 = new Thread(childref2);
            childThread2.Start();
            Console.ReadKey();
        }

        //監視線程，搶購結束後關閉所有線程
        public static void LookAtActiveThread()
        {
            DateTime TempDT = new DateTime();
            int totalCount = GoodsStock;
            while (true)
            {
                if (GoodsStock == 0 && payq.Count == 0 && waitq.Count == 0)
                {
                    TimeSpan ts = DateTime.Now.Subtract(TempDT);
                    Console.WriteLine("搶購活動已結束，" + totalCount + "個商品已在" + ts.Seconds + "秒售罄 當前時間：" + DateTime.Now);
                    break;
                }
                else
                {
                    Thread.Sleep(100);
                }
            }
        }

        //購買用戶隨機排隊插入隊列 排隊總人數不能超過10個
        public static void UserBuyInsertThread()
        {
            try
            {
                while (true)
                {
                    if (GoodsStock > 0)
                    {
                        //判斷等待隊列是否為空，付款隊列是否已滿，直接加入到付款隊列中
                        if (waitq.Count==0 && payq.Count < GoodsStock)
                        {
                            int userid = r.Next(10000, 99999);
                            payq.Enqueue(userid);
                            Console.WriteLine("用戶" + userid + "下單成功，請盡快付款 當前付款隊列：" + payq.Count + " 當前時間：" + DateTime.Now);
                            Thread.Sleep(r.Next(100));
                        }
                        else
                        {
                            int userid = r.Next(10000, 99999);
                            waitq.Enqueue(userid);
                            Console.WriteLine("用戶" + userid + "已加入到等待隊列中 當前等待隊列：" + waitq.Count + " 當前時間：" + DateTime.Now);
                            Thread.Sleep(r.Next(500, 2000));
                        }
                    }
                    else
                    {
                        Console.WriteLine("對不起，您來晚了，商品已售罄");
                        Thread.Sleep(300);
                    }
                    if (GoodsStock == 0 && payq.Count == 0 && waitq.Count == 0)
                    {
                        //停止線程
                        Console.WriteLine("排隊線程結束 當前時間：" + DateTime.Now);
                        break;
                    }
                }
            }
            catch (ThreadAbortException e)
            {
                Console.WriteLine("用戶排隊線程出錯了：" + e.ToString());
            }
        }

        //用戶購買操作，付款時間比較隨機
        public static void UserPayEndThread() 
        {
            try
            {
                while (true)
                {
                    if (payq.Count == 0 && waitq.Count == 0)
                    {
                        Thread.Sleep(300);
                    }
                    else
                    {
                        if (GoodsStock == 0)
                        {
                            if (waitq.Count > 0)
                            {
                                int userid = (int)waitq.Dequeue();
                                Console.WriteLine("對不起" + userid + "，商品已被搶購一空！ 下次請努力！ 當前時間：" + DateTime.Now);
                                Thread.Sleep(100);
                            }
                        }
                        else
                        {
                            if (payq.Count > 0)
                            {
                                int userid = (int)payq.Dequeue();
                                //用戶一定概率的超時或者取消訂單
                                if (r.Next(1, 10) < 3)
                                {
                                    Console.WriteLine("對不起，用戶" + userid + "已超時或取消訂單！ 當前付款隊列：" + payq.Count + " 當前時間：" + DateTime.Now + " 當前庫存：" + GoodsStock);
                                }
                                else
                                {
                                    GoodsStock -= 1;
                                    Console.WriteLine("恭喜！用戶" + userid + "已結賬，購買成功！ 當前付款隊列：" + payq.Count + " 當前時間：" + DateTime.Now + " 當前庫存：" + GoodsStock);
                                }
                                //把等待隊列中的用戶加入到付款隊列中，判斷付款隊列中是否超過庫存數量s
                                if (GoodsStock > 0 && GoodsStock > payq.Count && waitq.Count > 0)
                                {
                                    userid = (int)waitq.Dequeue();
                                    payq.Enqueue(userid);
                                    Console.WriteLine("用戶" + userid + "已從排隊隊列加入到付款隊列，請盡快付款！當前付款隊列：" + payq.Count + " 當前時間：" + DateTime.Now + " 當前庫存：" + GoodsStock);
                                }
                                Thread.Sleep(r.Next(100, 500));
                            }
                        }
                    }
                    if (GoodsStock == 0 && payq.Count == 0 && waitq.Count == 0)
                    {
                        //停止線程
                        Console.WriteLine("付款線程結束 當前時間：" + DateTime.Now);
                        break;
                    }
                }
            }
            catch (ThreadAbortException e)
            {
                Console.WriteLine("用戶結賬線程出錯了：" + e.ToString());
            }
        }
    }

C# 多線程與隊列操作小練刀