Regex - preg_match

[glenelkins]

Hi

 

Lets say i have the following string

 

Before{block}After

 

and the following preg_match

 

$content = "Before{block}After";

preg_match ( '%([A-Za-z0-9]*){(.*)}([A-Za-z0-9]*)%', stripslashes ( $content ), $data );

 

Works perfect, picks out $data[1] = "Before"  $data[2] = "block" $data[3] = "After"

 

But, say i have this

 

Before{block}After{block}

 

it doesnt work, it doesnt seem to pick up that i need to have $data[1] = "Before" $data[2] = "block" $data[3] = "After" $data[4] = "block"

 

Any help would be great

[salathe]

Depending what exactly you need, there might well be several different "answers" to your problem.  Do you literally just want to amend the regular expression to accept that second {block}, or any number of {block}s with before/after text, or ... ?

[.josh]

Are you looking to just grab everything that is not within {block} ?

[glenelkins]

hi

 

i am wanting to grab everything outside the {block} and the {block} itself.

 

so for example the actual thing may look like this

 

Some text {block identifier='test'} some more text {block identifier='another_test'}

 

and so on. My code is basically used so i can take the {block} tags and read the identifier and load up a plugin in my php based on what the identifier is set to, perform the code operation and replace the whole {block} tag...

 

But for now, im trying to get it to identify any number of block tags

 

 

[Garethp]

<?php

$content = "Before{block}After{blockb}Now{Blockc}A";

preg_match_all('~([a-zA-Z0-9]+)(?:{(.+?)})?~', stripslashes ($content), $tdata );

$data = array();

foreach($tdata[2] as $k=>$v)
{
$data[] = $tdata[1][$k];
if($v != "")
	{
	$data[] = $v;
	}
}

print_r($data);

?>

[fooDigi]

if your goal is to figure out what identifiers are used... this will return an array of identifiers stored in $matches[1]...

 

<?
$str = "before text{block identifier='test'}middle text{block identifier='test2'}end text";
preg_match_all("/{block identifier='([^']+)'}/",$str,$matches);
print_r($matches[1]);
?>

[glenelkins]

fooDigi

 

Even with all the years programming i have done, i still have a big issue with getting to grips with regex. Could you possibly break down your example and tell me what its doing. the [^']  part i understand, butut what is the + for?

[fooDigi]

sure. the plus char will basically match one or more instances of the previous expression... basically will match one or more characters that are not single quotes...

[fooDigi]

also, since you will want to replace the entire {block}, $matches[0] will contain those matched strings... so from there you will be able to replace those with the output of your plugins...

 

forgive me, but i went a bit further with my code, and i might as well post it... ignore it, if it is a total miss on what you need...

 

<?

function loadPlugin($id)
{
switch($id)
{
	case 'test':
	return '[plugin test loaded]';
	break;
	case 'test2':
	return '[plugin test2 loaded]';
	break;
	case 'test3':
	return '[plugin test3 loaded]';
	break;
	case 'test4':
	return '[plugin test4 loaded]';
	break;
	default:
	return '[invalid plugin]';
}
}

$str = "before text{block identifier='test'}middle text{block identifier='test2'}end {block identifier='test3'}text{block identifier='test4'}sdfasd fasdf asdf";
preg_match_all("/{block identifier='([^']+)'}/",$str,$matches);

for($i=0;$i<count($matches[0]);$i++)
{
$text = loadPlugin($matches[1][$i]);
$str = str_replace($matches[0][$i],$text,$str);
}

echo $str;
?>

[glenelkins]

hi

 

well i thought .*  matches any character any number of times? or are you saying + matches between []

[Garethp]

Okay, + is the same as * except * will match it 0 times. So say you have {} then {(.*)} will match it, but + matches once or more so {(.+)} will not, because there has to be at least one thing there.

 

Recap:

 

* Matches 0 or more

+ Matches 1 or more

[nrg_alpha]

glenelkins, you can read more about regex in general in the following links:

 

http://www.phpfreaks.com/tutorial/regular-expressions-part1---basic-syntax

http://www.regular-expressions.info/

http://weblogtoolscollection.com/regex/regex.php

 

These should be more than enough to get things started.. then, if you really want to get on the ball;

http://www.amazon.com/Mastering-Regular-Expressions-Jeffrey-Friedl/dp/0596528124/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1239475391&sr=8-1