C#单例模式

   public class Singleton
    {
       //定义一个全局私有变量
       private static Singleton _singletomn;
       private static int iCount;

      

       //定义一个只读的静态对象，为类创建时创建
       private static readonly object _lockObj = new object();

       /// <summary>
       ///  构造函数为内部的，外部不可实例化
       /// </summary>
       private Singleton() {}


       public static int Count {
           get { return iCount; }
       }


       /// <summary>
       /// 定义一个全局访问点
       /// </summary>
       /// <returns></returns>
       public static Singleton GetInstance() {
           iCount ++;

           //保证只能实例化一次
           if (_singletomn == null)
           {
               lock (_lockObj)
               {
                   if (_singletomn==null)
                   {
                       _singletomn = new Singleton();
                   }
               }
           }
           return _singletomn;
       }
    }

class Program
    {
        static void Main(string[] args)
        {
             Console.Write(Singleton.Count);
             Console.ReadKey();
        }
    }