using PERL regex in PHP

How would I do this?

[adni18]

Hi. I'm rather new to PHP, and I need to know how I would go about doing the following:

I have a directory with a bunch of files in it (images). What I want to do is have PHP replace all the tags that look something like

[hi.gif]

with

<img src="emoticons/hi.gif">

but ONLY if the file exists. How could I do the replacement?

Is there some way to reference to a certain grouping of regex stuff, like in perl? ($1)

Please respond ASAP.

[Longhaired Genius]

PHP includes Perl-compatible regular-expressions:
[docs.php.net...]

[adni18]

So how would something like this be done in PHP (this is perl syntax)?

$string=~s/(\[.{1,}\])/checkimg($1)/g;

[dmorison]

You'd use preg_replace() [uk.php.net] something like:

$string = preg_replace("/(\[.{1,}\])/g","checkimg($1)",$string);

[adni18]

thanks!

[adni18]

Ah! That replaces the $1, but how do I make it replace it with the return value of a PHP function, with the parameter of $1?

[dmorison]

$string = preg_replace("/(\[.{1,}\])/ge","checkimg($1)",$string);

...the e modifier causes the replacement string to be interpreted as PHP code.

[adni18]

...also had to add quotes before and after $1...

checkimg(\"$1\")

Thanks!

[adni18]

Grrr. For some reason the /g modifier isn't working. Any workaround?

[coopster]

preg_replace() [php.net] searches the subject for matches to the pattern and replaces every such reference with the replacement. The /g modifier is not valid here, it is already global.

[adni18]

PHP doesn't seem to want to replace all the instances, though. Whenever there is more than one instance, it doesn't do anything.... :(

[coopster]

Can you offer an example of the string you are searching and the pattern you are using?