有个时候需要读取layouts下的xml文件，因此需要知道路径，以前在SP2010用的SPUtility.GetGenericSetupPath()方法获取。现在SP2013提示过期否决
看2个结构分析
在SP2013使用SPUtility.GetVersionedGenericSetupPath().
For an example of how this can effect you code - look below. This code is returning a Url to one of our pages that's deployed to the layouts folder. If we had not made change to include the "15" it would have pointed to the 14 hive - which is good for a 2010 solution running on 2013, but not good for us