实体框架继承关系。很好

http://www.cnblogs.com/Barton131420/archive/2009/09/04/1560237.html

 

http://weblogs.asp.net/zeeshanhirani/archive/2008/08/16/single-table-inheritance-in-entity-framework.aspx

 

truning  json into a expand object

 

http://coderjournal.com/2010/07/turning-json-into-a-expandoobject/