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Regex: Functionality about named/numbered groups everyone should know.

We have a cool new tool amongst us over on http://www.regexlib.com/RETester.aspx . It is already more functional than the previous tool there that was receiving quite a bit of traffic and attention for quickly testing expressions. The new tool really...

The power available in regular expressions always amazes me.

Been spending a portion of the day on the MS newsgroups helping people out. I figure I'll get bonus points when I'm dead for helping people on Easter rather than searching for eggs and eating candy (just kidding my friends, just kidding). I was starting...
Posted by Justin Rogers | with no comments

Performance: Different methods for testing string input for numeric values...

So there was a blog entry about the VB .NET IsNumeric function today. The question was in regards to a C# equivalent. I have two things to say really. First, if you really want the IsNumeric function from VB you can always grab it out of Microsoft.VisualBasic...

Making the Regex engine choke... Ever wanted to? I'll show you how...

Okay, so back in the pre-V1 days I made a humongous regular expression alternation group and wanted to precompile that guy for maximum speed. What exactly is a humongous regular expression? Well imagine 12000 or so words, each on average of 10 characters...

Want faster regular expressions? Maybe you should think about that IgnoreCase option...

Let me start with a disclaimer. RegexOptions.IgnoreCase is a very powerful option that allows you to match ignore character casing during matches irregardless of the currently running culture. In other words, this will allow you to take into account other...

Match vs MatchSparse, a regular expression implementation detail that may surprise you.

So out of the blue I printed the type of a Match, and found it wasn't a Match, but instead a MatchSparse. Okay, now I have to go look up the difference. It appears that a MatchSparse is created when you don't have sequentially ordered numeric capture...
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