C#：lock锁与订单号（或交易号）的生成

 1     /// <summary>
 2     /// 订单助手
 3     /// </summary>
 4     class OrderIdHelper
 5     {
 6         private static readonly object Locker = new object();
 7         private static string _tempId = "";
 8 
 9         /// <summary>
10         /// 生成订单编号
11         /// </summary>
12         public static void GenerateId()
13         {
14             lock (Locker)   //lock 关键字可确保当一个线程位于代码的临界区时，另一个线程不会进入该临界区。
15             {
16                 var orderId = "Wen" + DateTime.Now.ToString("yyyyMMddHHmmss");  //年月日时分秒
17 
18                 if (string.Equals(_tempId, orderId))
19                 {
20                     throw new Exception("订单号重复！");
21                 }
22 
23                 _tempId = orderId;
24 
25                 Console.WriteLine(orderId);
26             }
27         }
28     }

 1     class Program
 2     {
 3         static void Main(string[] args)
 4         {
 5             //创建包含两个线程的数组
 6             var threads = new Thread[2]
 7             {
 8                 new Thread(OrderIdHelper.GenerateId),
 9                 new Thread(OrderIdHelper.GenerateId),
10             };
11 
12             foreach (var thread in threads)
13             {
14                 //线程启动
15                 thread.Start();
16             }
17 
18             Console.Read();
19         }
20     }