Re: [PHP] regex usage

[Richard Lynch]

On Sun, February 17, 2008 9:34 am, Valedol wrote:
 Is there a mothod to check string`s length with regex or the only way
 is
 using strlen?

 I want string consisting of 4 digits
 and check string with this code:

 if (preg_match(/\d{4}/,$_POST[id]))
 { echo $_POST[id]; }

 but preg_match  returns true when string consists of 4 or more digits

Actually, it will return true for anthing with 4 consecutive digits
anywhere inside it, including:

abc1234def

You want:
/^\d{4}\$/
if you want EXACTLY 4 digits and nothing more.

^ anchors the string at the start
$ anchors the string at the end

The \ in front of $ is because $ is PHP for a variable, and while
there are not characters after it, so it's NOT a variable today, you
might add some on another day...

-- 
Some people have a gift link here.
Know what I want?
I want you to buy a CD from some indie artist.
http://cdbaby.com/from/lynch
Yeah, I get a buck. So?

-- 
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] regex usage

[Shawn McKenzie]

Valedol wrote:
 Is there a mothod to check string`s length with regex or the only way is
 using strlen?
 
 I want string consisting of 4 digits
 and check string with this code:
 
 if (preg_match(/\d{4}/,$_POST[id]))
 { echo $_POST[id]; }
 
 but preg_match  returns true when string consists of 4 or more digits


preg_match(/^\d{4}$/,$_POST['id'])

-- 
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] regex usage

[Richard Heyes]

Is there a mothod to check string`s length with regex or the only way is 
using strlen?


I want string consisting of 4 digits
and check string with this code:

if (preg_match(/\d{4}/,$_POST[id]))
{ echo $_POST[id]; }

but preg_match  returns true when string consists of 4 or more digits


You could change the regex to use start/end anchors. Also, the trailing 
comma in the length specifier bit means 4 or more Eg:


if (preg_match(/^\d{4,}$/, $_POST['id'])){
echo $_POST['id'];
}

--
Richard Heyes
http://www.websupportsolutions.co.uk

Knowledge Base and Helpdesk software hosted for you - no
installation, no maintenance, new features automatic and free

 ** New Helpdesk demo now available **

--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] regex usage

[Nirmalya Lahiri]

--- Valedol [EMAIL PROTECTED] wrote:

 Is there a mothod to check string`s length with regex or the only
 way is  
 using strlen?
 
 I want string consisting of 4 digits
 and check string with this code:
 
 if (preg_match(/\d{4}/,$_POST[id]))
 { echo $_POST[id]; }
 
 but preg_match  returns true when string consists of 4 or more
 digits
 -- 

To check only 4 digit, you have to specify max lengh of the string in
length specifier..

if (preg_match(/\d{4,4}/,$_POST[id]))
 { echo $_POST[id]; }

---
Nirmalya Lahiri
[+91-9433113536]


  

Looking for last minute shopping deals?  
Find them fast with Yahoo! Search.  
http://tools.search.yahoo.com/newsearch/category.php?category=shopping

-- 
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] regex usage

[Jim Lucas]

Valedol wrote:
Is there a mothod to check string`s length with regex or the only way is 
using strlen?


I want string consisting of 4 digits
and check string with this code:

if (preg_match(/\d{4}/,$_POST[id]))
{ echo $_POST[id]; }

but preg_match  returns true when string consists of 4 or more digits


Yes you can, but why do it this way?  What advantage is it over the 
following?


Given that this isn't a real intense regex, I don't know how much you 
will save, but you could also do this.


if ( strlen(intval($_POST['id'])) == 4 ) {
echo $_POST['id'];
}

Not sure about speed, but it might be a little faster if you are looking 
for performance.


Jim Lucas

--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php