How to extract a substring from a .NET RegEx?

Question

I have an XML file containing one (or more) key/value pairs. For each of these pairs I want to extract the value which is a two-byte hex value.

So the XML contains t

Answer 1

Add a grouping construct to your expression ...

(?LibID)([a-fA-F0-9]{4})

That will capture the ID. But, you need to put the correct format in your expression for the actual ID, because your regex will only capture "LibID" litterally.