如何对。net代码进行单元测试(允许重构)

I have been spinning my wheels now for awhile trying to figure out how I can possibly unit test the following code. At first I was going to use Moq to mock everything, but it doesn't include the ability to mock sealed classes. I know I need to abstract out the calls to the implementation (Configuration) using an interface? but I can't seem to make it all work right.I have been spinning my wheels now for awhile t