Regex nested forum quotes (BBCode)

Question

Possible Duplicate:
php regex [b] to <b>

I'm having trouble with regex, I'm an absolute regex noob. I can't see what's going wrong with trying to convert the HTML back to the 'BBCode'.

Could somebody take a look at the 'unquote' function and tell me the obvious mistake I'm making? (I know it's obvious because I always find the un-obvious errors)

NOTE: I'm not using recursive Regex because I couldn't get my head around it and already started this way round of sorting out the Quotes so they're nested.

<?php
function quote($str){
    $str = preg_replace('@\[(?i)quote=(.*?)\](.*?)@si', '<div class="quote"><div class="quote-title">\\1 wrote:</div><div class="quote-inner">\\2', $str);
    $str = preg_replace('@\[/(?i)quote\]@si', '</div></div>', $str);
    return $str;
}

function unquote($str){
    $str = preg_replace('@\<(?i)div class="quote"\>\<(?i)div class="quote_title"\>(.*?)wrote:\</(?i)div\><(?i)div class="quote-inner"\>(.*?)@si', '[quote=\\1]\\2',  $str);
    $str = preg_replace('@\</(?i)div\></(?i)div\>@si', '[/quote]', $str);
}
?>

This is just some code to help test it:

<html>
<head>
    <style>
    body {
        font-family: sans-serif;
    }
    .quote {
        background: rgba(51,153,204,0.4)  url(../img/diag_1px.png);
        border: 1px solid rgba(116,116,116,0.36);
        padding: 5px;
    }

    .quote-title, .quote_title {
        font-size: 18px;
        margin: 5px;
    }

    .quote-inner {
        margin: 10px;
    }
    </style>
</head>
<body>
    <?php
    $quote_text = '[quote=VCMG][quote=2xAA]DO RECURSIVE QUOTES WORK?[/quote]I have no idea.[/quote]';
    $quoted = quote($quote_text);
    echo $quoted.'<br><br>'.unquote($quoted); ?>
</body>

Thanks in advance, Sam.

score 3 · Accepted Answer · answered Oct 07 '12 at 22:23

Well, you could start by setting you php class to either quote-title or quote_title but keep it consistent.

Then, add a return $str; to your second function and you should be nearly there.

And you can simplify your regex's a little :

function quote($str){
    $str = preg_replace('@\[quote=(.*)\]@siU', '<div class="quote"><div class="quote-title">\\1 wrote:</div><div class="quote-inner">', $str);
    $str = preg_replace('@\[/quote\]@si', '</div></div>', $str);
    return $str;
}

function unquote($str){
    $str = preg_replace('@<div class="quote"><div class="quote-title">(.*) wrote:</div><div class="quote-inner">@siU', '[quote=\\1]',  $str);
    $str = preg_replace('@</div></div>@si', '[/quote]', $str);
    return $str;
}

But beware of replacing with different calls the start and end tags of your quotes. I thin that unquote can create some strange behaviours if you happen to have other bbcode creating </div></div> code.

>_> That goddamn return... I knew it was something obvious. And thank you for the simplification, much better! — 2xAA, Oct 07 '12 at 23:34

Niet the Dark Absol · Answer 2 · 2012-10-08T12:13:02.250

0

Personally, I take advantage of the fact that the resulting HTML is basically:

<div class="quote">Blah <div class="quote">INCEPTION!</div> More blah</div>

Repeatedly run the regex until there are no more matches:

do {
    $str = preg_replace( REGEX , REPLACE , $str , -1 , $c);
} while($c > 0);

Also, do it as one regex to make this easier:

'(\[quote=(.*?)\](.*?)\[/quote\])is'
'<div class="quote"><div class="quote-title">$1 wrote:</div><div class="quote-inner">$1</div></div>'

edited Oct 08 '12 at 12:13

answered Oct 07 '12 at 22:31

Niet the Dark Absol

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I think having read somewhere that using question marks "inverts greediness" of the quantifier, it does not simply make them lazy. So if the quantifiers are lazy because you used the U option, you made them greedy again by using `.*?` which is not what you would want. – Cimbali Oct 08 '12 at 08:07
Ah, yeah. I thought the U was the "unicode" one, but that's lowercase `u`. Okay, will edit. – Niet the Dark Absol Oct 08 '12 at 12:12

Regex nested forum quotes (BBCode)

2 Answers2