http://www.cnblogs.com/idior/archive/2005/08/09/210320.html
http://www.cnblogs.com/hBifTs/articles/9291.html
http://www.cnblogs.com/hBifTs/articles/9294.html
http://www.cnblogs.com/hBifTs/articles/9291.html
http://www.cnblogs.com/hBifTs/articles/9294.html