.net 4.0新特性-延迟初始化:Lazy(转),ThreadLocal

感谢作者
http://www.cnblogs.com/anytao/archive/2009/10/29/must_net_33.html

http://www.cnblogs.com/me-sa/archive/2010/05/25/lazy-initialization-fx4.html

.net也有ThreadLocal了

http://www.cnblogs.com/tmrcp/archive/2009/07/17/1525506.html

.net 4.0之前用ThreadStatic标签代替

http://msdn.microsoft.com/en-us/library/dd997286(v=VS.100).aspx

 

补充

1. ThreadStatic的使用情况

代码

     public   class  Demo7
    {
         static   int  count = 100000 ;
         public  Demo7()
        {
            ThreadPool.QueueUserWorkItem( new  WaitCallback(Task1));
            ThreadPool.QueueUserWorkItem( new  WaitCallback(Task2));
        }

         public   void  Task1( object  obj)
        {
             for  ( int  i  =   0 ; i  <   100000 ; i ++ )
            {
                count ++ ;
            }

            Console.WriteLine(DateTime.Now);
            Console.WriteLine( " Task1 count {0} " , count);
        }

         public   void  Task2( object  obj)
        {
             for  ( int  i  =   0 ; i  <   100000 ; i ++ )
            {
                count ++ ;
            }
            Console.WriteLine( " Task2 count {0} " , count);
        }
    }

 

 显示效果 

 

显示为乱数,其实不准的

2.使用了 ThreadStatic以后的结果

 

 即该变量已经成为线程的局部变量,初始化的值也重置了