http://www.cnblogs.com/panchunting/p/WebAPI_Demo.html
http://www.cnblogs.com/fzrain/p/3527765.html
http://www.cnblogs.com/guyun/p/4581297.html
http://www.jb51.net/article/74090.htm
http://blog.csdn.net/yuchen_0515/article/details/51678752
http://www.cnblogs.com/Leo_wl/p/5672430.html
返回json
gloabal.cs
加入下句
GlobalConfiguration.Configuration.Formatters.XmlFormatter.SupportedMediaTypes.Clear();