Every time I use regular expressions (or post about them), it makes me think about the classic RegEx post by Jeff Atwood: to compile or not to compile.
BTW: Happy 2013!
–jeroen
Archive for the ‘RegEx’ Category
.NET regular expressions classic: to compile or not to compile?
Posted by jpluimers on 2013/01/01
Posted in .NET, C#, C# 1.0, C# 2.0, C# 3.0, C# 4.0, C# 5.0, Development, RegEx, Software Development | Leave a Comment »
which kind of IsHex() function do you like most, and why?
Posted by jpluimers on 2012/07/10
Though the sample question is in C#, it applies to almost any language and framework: for relatively simple checks like IsHex(), you can go the RegEx way, or the compound if-statement way.
Which kind of function do you like most?
I’m not only interested in the percentages, so let me know in the comments why.
–jeroen
PS: if you want to use RegEx in .NET, you can compile them to IL, but be very cautious for the compilation overhead.
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Posted in .NET, C#, COBOL, Delphi, Development, JavaScript/ECMAScript, PHP, RegEx, Scripting, Software Development, VB.NET | 8 Comments »
Stack Overflow ebooks
Posted by jpluimers on 2011/02/10
Greg Hewgill published a bunch Stack Overflow ebooks and StackExchange stats.
His readme explains a bit more on the books.
The blog he maintains makes up for some nice reading too.
Be sure to read the blog entry on the ebooks.
–jeroen
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Posted in *nix, .NET, ASP.NET, C#, C# 2.0, C# 3.0, C# 4.0, Database Development, Delphi, Delphi for PHP, Development, HTML, HTML5, Java, Pingback, Power User, RegEx, Scripting, SocialMedia, Software Development, SQL, SQL Server, Stackoverflow, XML/XSD | Leave a Comment »
The hilarious answer on Stack Overflow in why not to parse html with RegEx
Posted by jpluimers on 2011/02/09
Quite a while ago, user bobince wrote great answer on why not to parse html with RegEx.
Somehow people fail to recognize the brilliance of the answer, and try to simplify it into something like “don’t, use an XML or HTML parser in stead”.
bobince even posted some nice contra-examples that are impossible to parse in RegEx (heck, even most regular HTML and XML parsers have difficulties with them).
So: enjoy the beauty of the answer while it is still locked for editing.
–jeroen
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Posted in Development, HTML, RegEx, Software Development, Web Development, XML, XML/XSD | 2 Comments »
Formatted sourcecode in WordPress: uses SyntaxHighlighter 3.0; complete list of supported languages
Posted by jpluimers on 2011/01/18
In the past I wrote a few blog posts on posting sourcecode in WordPress.
Nick Hodges‘ last Flotsam and Jetsam blog post pointed me to the SyntaxHighlighter JavaScript that is used by WordPress and many other engines/sites.
Their site contains an even more elaborate list of supported languages.
I had the basic list right in my last post, but was missing all the aliases (which often are easier than the longer proper names).
This is the new table adapted from their list: Read the rest of this entry »
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Posted in .NET, Batch-Files, C#, CSS, Database Development, Delphi, Delphi for PHP, Development, HTML, HTML5, Java, PowerShell, RegEx, Scripting, SQL, VBS, Web Development, WordPress, XML, XML/XSD, XSD | 5 Comments »
Regular expressions and the ASP.NET RegularExpressionValidator control – an overview of useful links
Posted by jpluimers on 2009/09/10
Every now and then I need the ASP.NET RegularExpressionValidator control to validate some user input on a web-page using .NET Regular Expressions (which are very similar to regular expressions used in other languages and frameworks).
Somehow, I have lost loads of time because many of the hits on Google show up high in the results, but do not actually help that much.
So I decided to put up a bunch of links to pages that I think are relevant, or helped me much.
This list is not definitive: please comment when you have links to better information!
Note: this list is current at the instant of the latest edit timestamp: tools might have improved (or disappeared) since then.
Opnions are mine; if you do not agree: please convince me why.
Tools
Regular Expression builder applications
- Expresso – free .NET WinForms application to visually build and test regular expressions (free registraion required after 60 days of trial usage)
- RegexWorkbench – free .NET WinForms application to build and test regular expressions (much more rudimentary than Expresso)
Regular Expression test applications
- RegexLib tester – free on-line regular expresion tester where you can choose the client platform (.NET/ClientSide/SilverLight)
- The Regulator – free .NET WinForms application to test regular expressions with built in support for RegexLib.com
- The Regex Coach – free LISP Windows application to test regular expressions and tries to explain them in plain english
- RegExPal – free on-line JavaScript regular expression tester (tests the client side only)
- ReWork – free on-line JavaScript tester with samples in JavaScript/PHP/Python/Ruby
- RegexDesigner.NET – free .NET WinForms application to test regular expressions and generate C#/VB.NET code from them (ot really a “Designer” after all and much less sophisticated than The Regulator)
Tools lists
- SharpToolbox – list of Regular Expression tools
- RegexLib – list of regex resources, including tools
Tools not worth looking at
- Regulazy – too rudimentary
Sites/Documentation/Examples
- The well respected RegexLib.comsite:
- CheatSheet of how regular expressions can be built
- Search for regular expressions
- Browse regular expressions
- MSDN documentation on JScript Regular Expressions – I wish this was more readable, but it is the definitive source on Microsoft’s JScript Regular Expression implementation
MSDN documentation on the .NET Framework Regular Expressions, including
Regular Expression Language – Quick Reference.
Grouping Constructs in Regular Expressions.
Anchors in Regular Expressions. - The 30 Minute Regex Tutorial – CodeProject.
- C# Regular Expressions Cheat Sheet.
- RegEx questions on Stackoverflow.com
- Nice tutorial on regular expressions
- Stackoverflow thread on writing maintanable regular expressions (if that is at all possible <g>), with many good tips
- Stackoverflow thread on why regular expressions usually look so cryptic (which make them hard to read and write), including some tips on making them more readable
- JavaScript: Unicode Plugin for XRegExp
Some comments on common regular expression solutions
- RegEx for email usuaully reject valid email adresses like jeroen+info@pluimers.subdomain.info
Dominic has some very nice info on validating email adresses - RegEx for a minimum number of characters usually contain \w, which is not any character!
Better use ^(.{6,})$ than ^(\w{6,})$ if you want a minimum length of 6 characters.
Bugs
- JScript/VBScript bug that is also present in Internet Explorer (almost any version): A JScript/VBScript Regex Lookahead Bug
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Posted in .NET, ASP.NET, Development, Encoding, JavaScript/ECMAScript, LISP, RegEx, Scripting, Software Development, Unicode, Web Development | Leave a Comment »
The Wiert Corner - irregular stream of stuff 