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.net 4.0新特性-延迟初始化:Lazy(转),ThreadLocal<T>

2010-06-09 22:59  Clingingboy  阅读(1298)  评论(1编辑  收藏  举报

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