.NET 设计模式之单例模式（一）

public class Singleton{
  private static Singletom _singleton = null;
  //锁
  private static Object singleton_lock = new Object();
  //构造函数私有化
  private Singleton(){
      //初始化代码
  }
  public static Singleton CreateInstance(){
     if(_singleton == null) //先看看是否初始化过，避免每次进入都要判断锁
     {
        lock(_singleton_lock){  //防止多个线程进入
            if(_singleton == null){  //判断单例对象是否为null
               _singleton = new Singleton();
            }
        }
     }
     return _singleton;
  }
}