Regular Expressions

Date Published: 06 February 2003

Regular Expressions

Regular expressions are very powerful, and are one of my favorite tools to use because they are so flexible and they can be used regardless of whether one is a .NET developer or a Unix shell scripter or a Java developer or whatever. As I started getting into regular expressions for validation controls, I noticed that there wasn’t any online library for these expressions, which of course meant that a lot of people were reinventing the wheel. How many times do different people need to come up with the same (or very close) expression for an email address or a ZIP code, for crying out loud? So I used this problem to test out my then-novice ASP.NET skills and created an online regular expression library,

RegExLib is now over a year old and has quite a few expressions listed and a decent amount of traffic each week. I’m looking for ideas for how I can improve it. Since I’ll be speaking on regular expressions in May at ASP.NET Connections, and I intend to provide attendees with a regex cheat sheet, one feature I intend to add to the site is the cheat sheet I’ll be handing out (as a printable web page). I also am aware of a few bugs that need fixed – those are on hold until my Cookbook is done (see yesterday for more on that…).

Anyway, since I’m sure I have a huge audience reading this, please check out and let me know what you think and how I could make it better. It really is just a simple little app at the moment with perhaps 15-20 hours of time invested in it. Since it’s getting popular and has enough expressions to make it somewhat useful now, I’m interested in putting some more time into it to make it better. Thanks for any constructive input.

Steve Smith

About Ardalis

Software Architect

Steve is an experienced software architect and trainer, focusing on code quality and Domain-Driven Design with .NET.