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php_wiz_kid
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PostPosted: Sun Nov 27, 2005 2:15 am 
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Wonderful tutorial. Espcially to regex noobs like me. This got my form validation working. Good job.
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infolock
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PostPosted: Sun Nov 27, 2005 2:46 am 
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greatest tutorial on regex on the net imo.

great job.
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Luke
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PostPosted: Fri Dec 16, 2005 2:53 pm 
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great tutorial! my only question...
Quote:
One last thing before we build our first regex. Regex needs to be delimited if using Perl style regular expressions (preg_match()) which I strongly advise you do (Note: ereg_...() is not perl style).

To delimit a regex we start and end with the EXACT same character. The two standards are (but you can use most non-alphanumeric characters):
Code:

/pattern/
#pattern#

Why does it have to be delimited? What does that mean?
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twigletmac
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PostPosted: Fri Dec 16, 2005 3:26 pm 
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The Ninja Space Goat wrote:
Why does it have to be delimited? What does that mean?

Delimiters mark the beginning and end of a pattern - if you use pattern modifiers then they would be added after the ending delimiter. The delimiter you'll probably see most often is a forward slash (/).
Quote:
To delimit a regex we start and end with the EXACT same character. The two standards are (but you can use most non-alphanumeric characters):
Code:

/pattern/
#pattern#

Mac
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julian_lp
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PostPosted: Fri Jul 28, 2006 6:24 pm 
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infolock wrote:
greatest tutorial on regex on the net imo.

great job.



Absolutely true. I ask myself why I didn't find it before.
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Shendemiar
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PostPosted: Sun Aug 06, 2006 6:16 pm 
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Actually, this is best Regexp tutorial i've come across with!

I made this in notime, and just 15 minutes ago it seemed impossible!

Syntax: [ Download ] [ Hide ]
 
        # Cut out linefeeds and whitespace around them!
        $value = preg_replace("#\\s{0,}\\r\\n\\s{0,}#", "", $value);
 


I think it was not mentioned, that PHP itself, needs to escape few characters as well, like the Regexp escape character \ or ", with the php escape char: (also) \

So in other words, if your regexp is
Syntax: [ Download ] [ Hide ]
 
#\s{0,}\r\n\s{0,}#
 


in php it needs to be
Syntax: [ Download ] [ Hide ]
 
#\\s{0,}\\r\\n\\s{0,}#
 


Last edited by Shendemiar on Fri Apr 25, 2008 12:35 pm, edited 1 time in total.

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Chris Corbyn
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PostPosted: Mon Aug 07, 2006 5:38 am 
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Shendemiar wrote:
I think it was not mentioned, that PHP itself, needs to escape few characters as well, like the Regexp escape character \ or ", with the php escape char: (also) \


Well spotted ~Shendemiar :) That's very true. The same is true in JavaScript when creating a regexp object by using the syntax var re = new RegExp();. JavaScript is a little more friendly however since you don't need to use a string to make a pattern, you can do it literally:

Syntax: [ Download ] [ Hide ]
var re = /patterns?/; //No quotes needed so only one \ needed to escape


Perl is also friendly in this sense too:

Syntax: [ Download ] [ Hide ]
if ($string =~ /sun(?!shine)/i)
{
    print "$string contains the word "sun" but not the word "sunshine"";
}


PHP however always requires the use of a string.
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feyd
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PostPosted: Mon Aug 07, 2006 8:10 am 
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That's why I use single quotes for my regex pattern strings.. almost all strings really.
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aqualodge
 Post subject: It still works
PostPosted: Thu Mar 08, 2007 4:34 am 
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Great tutorial ... Really helps. Your'e all experts.. :D
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yacahuma
 Post subject: Excelent tutorial here
PostPosted: Tue Aug 21, 2007 1:30 pm 
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This is an excellent tutorial.

[url]
http://www.webcheatsheet.com/php/regula ... ssions.php
[/url]
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beemzet
PostPosted: Sun Sep 02, 2007 11:04 pm 
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yacahuma wrote:
This is an excellent tutorial.

[url]
http://www.webcheatsheet.com/php/regula ... ssions.php
[/url]


yeah, it is.

Other links:
http://www.phpbuilder.com/columns/dario19990616.php3

http://www.vinuthomas.com/News/article/sid=416.html
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GeertDD
PostPosted: Wed Sep 26, 2007 1:35 pm 
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d11wtq wrote:
Syntax: [ Download ] [ Hide ]
Character         Matching

. (dot)           ANY single character at all

Syntax: [ Download ] [ Hide ]
Modifier         Effect

s                Ignore whitespace


Note that the above is not quite true.

The dot metacharacter does match any single character except for newlines.

I don't know exactly what you mean by 's modifier ignores whitespace'? Anyway, the s modifier just changes the meaning of the dot metacharacter which will then match newlines as well. Agree?
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crespowu
PostPosted: Thu Jan 17, 2008 3:56 am 
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Great content.
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batfastad
PostPosted: Thu Jan 22, 2009 8:47 am 
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This is a great tutorial. I refer to it all the time.

However I think I've found one slight inaccuracy regarding the s modifier which could be updated.

I use the regex coach utility to check out what's happening, and its explanation of the s modifier is "Treat string as single line"
When I was building a regex recently, the tutorial had me wondering why it wasn't working when I used the m modifier as I didn't think the s one was for me. As soon as I switched to the s modifier after looking at that bit on the regex coach, it worked straight away.

Cheers, B
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papa
PostPosted: Thu Jan 22, 2009 9:02 am 
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Very nice tutorial!
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