http://blog.csdn.net/u011012932/article/details/51029602
http://blog.csdn.net/u011012932/article/details/51029511
http://blog.csdn.net/u011012932/article/details/51027099
http://blog.csdn.net/u011012932/article/details/51029355
原文：http://www.cnblogs.com/findumars/p/5962300.html