.NET port of dk.brics.automaton - Project Fare is an effort to bring a DFA/NFA (finite-state automata) implementation from Java to .NET. There are quite a few implementations available in other languages today. This project aims to fill the gap in .NET.
The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5. The PCRE library is free, even for building proprietary software.
PCRE homepage: http://pcre.org/
OFFICIAL VerbalExpression package. This is a fluent regex builder. This comes from the official updated VerbalExpression/CSharpVerBalExpressions on github. https://github.com/VerbalExpressions/CSharpVerbalExpressions