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Regex Hero's Debut

So last week I launched and submitted it to a few social bookmarking sites ( happened to be the most effective). Since then I've had 368 visits to the site. That's a pretty strong start for a brand new website.

What Does The Tool Do?
Regex Hero will dynamically highlight regular expression matches as you type. The whole idea behind it is to save as much time as possible and make it as convenient as possible to work with regular expressions.

What's Special About It?
It's the first online .NET regular expression tester with instantaneous highlighting that I know of. (Someone please correct me if I'm wrong.) Microsoft Silverlight lends itself to this functionality perfectly. I essentially wrote it and got it online in 3 days. Since then I've made some tweaks and minor improvements, but nevertheless it was extremely easy to build and I have to thank Microsoft and their development tools for that.

The other thing I was surprised about is just how well .NET regular expressions are optimized. You can see for yourself if you use the benchmark feature in Regex Hero. On my computer it'll perform regular expression matching 500,000 times in one second, easy. The way .NET compiles and caches regular expression seems to really make it scream. That kind of performance helps with the instantaneous highlighting. I mean, you can create a huge target string and it'll still find and highlight the matches within milliseconds after every key press.

Will it Always be Free?
That's a tough question. Most likely, the online version you see now will always be free. But I may at some point create a desktop (WPF) version that I'll sell for cheap.

What's Coming Next?
I'm trying to figure out how to display the exception properly when you write an invalid regular expression. Essentially, since Silverlight excludes the necessary debugging assemblies, it won't provide the same exception detail I'm used to. Once I get that figured out you should see better error messages.

Then the next thing for me to do is add the ability to replace text with regular expressions. Other than that, I'm open to suggestions.


  1. Hey, not that it's a work of art like Regex Hero (kudos) but there is another Silverlight Regular Expression tool - a variant of my tool nregex ( called nregex9 at:

  2. Thanks David.

    That's one I missed. I remember finding your site but I guess I missed your Silverlight version. Google searching > me.


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