Cannot attach the file as database这个异常是在EF的code frist里经常出现的,解决方法很简单,只要重新启动一下V11实例即可。
CMD> sqllocaldb.exe stop v11.0
LocalDB instance "v11.0" stopped. CMD>
CMD> sqllocaldb.exe delete v11.0
LocalDB instance "v11.0" deleted. CMD> sqllocaldb.exe start v11.0
LocalDB instance "v11.0" started.