preg_replace: $1 in pattern?

[j0sh]

hi all.

i'd like to convert bb-code with the following code:

<?php

$text = "
[i]hallo[/i]
";

function convertSimplicityCode($text) {
	$text = preg_replace("/\[([biu])\](.*)\[\/([$1])\]/i","<$1>$2</$1>",$text);
	return $text;
}

echo "<textarea>".convertSimplicityCode($text)."</textarea>";

?>

but it does not seem to work with the $1. 🙁

it works using

preg_replace("/\[([biu])\](.*)\[\/([biu])\]/i","<$1>$2</$1>",$text);

but then it will also parse

hello[/i]

as <u>hello</u>

is it not possible to use $1, $2 etc. in the preg_match pattern?

thank you for info. 🙂

[laserlight]

/[([biu])](.)[\/([$1])]/i
should be:
/[([biu])](.)[\/($1)]/i

The former fails because you substituted $1 for biu instead of [biu]

[j0sh]

thanks, but it still does not work:

$text = preg_replace("/[([biu])](.*)[\/($1)]/i","<$1>$2</$1>",$text);

[laserlight]

I think that you should use \1 instead of $1 for the 1st back-refererence as it is more standard, and use single quotes to delimit the pattern string so that PHP will not parse the escape sequences within it.

$text = "[i[i][/i]]hallo[/i[i][/i]]";

function convertSimplicityCode($text) {
	$text = preg_replace('/\[([biu])\](.*)\[\/(\1)\]/i','<\1>\2</\1>',$text);
	return $text;
}

echo "<textarea>".convertSimplicityCode($text)."</textarea>";

[j0sh]

wow now it works! thank you very much, you are really a php witch! 🙂

only one question: why is there a difference using " or using ' as quotes? with " it really does not work, but with ' it does... 😕

have a nice time @ singapore! 🙂

[Weedpacket]

Originally posted by j0sh
only one question: why is there a difference using " or using ' as quotes? with " it really does not work, but with ' it does... 😕

Because in double-quoted strings there are a lot more escape sequences recognised, including ones that start with a digit.