C#设计模式-单例模式

 1     class Singleton
 2     {
 3         private static Singleton instance;
 4         private static readonly object syncRoot = new object();
 5         private Singleton()
 6         {
 7         }
 8 
 9         public static Singleton GetInstance()
10         {
11             if (instance == null)
12             {
13 
14                 lock (syncRoot)
15                 {
16 
17                     if (instance == null)
18                     {
19                         instance = new Singleton();
20                     }
21                 }
22             }
23             return instance;
24         }
25 
26     }

 1   static void Main(string[] args)
 2         {
 3             Singleton s1 = Singleton.GetInstance();
 4             Singleton s2 = Singleton.GetInstance();
 5 
 6             if (s1 == s2)
 7             {
 8                 Console.WriteLine("Objects are the same instance");
 9             }
10 
11             Console.Read();
12         }