How to deal with a sealed class when I wanted to inherit and add properties

Question

In a recent question on Stack Overflow, I asked how I might parse through a file name to extra meta info about a file.

After I worked through that problem, I decided

Answer 1

This is one of the classic composition instead of inheritance examples and you went in the right direction.

To solve your property problem just create a property called Length that delegates to the encapsulated FileInfo object.