http://blog.csdn.net/mywcyfl/article/details/37765751
http://blog.csdn.net/teng_ontheway/article/details/38900211
http://www.cnblogs.com/howeho/p/4048201.html
http://www.jb51.net/article/55171.htm
https://blog.csdn.net/sq2108/article/details/40340725