Rexer (nuget): Rexer is an awesome regex lexer library that fulfills your needs easily! It's also open-source so if you ever find a bug, you can fix it(and make a pull request on the Github.)  The functions and classes are all well documented so you will not have much trouble settings things up. Alternatively there is a test program in the Github to lead you in the right direction.  Website + Documentation Coming Soon.
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