How to delete a piece of string in PHP using regular expressions?

Question

I'm new to PHP and today I found this problem. I have this string:

442_38489_ext/index.php

I want to delete a piece of the string: from end of it to first backslash (in this case /index.php), using only regular expressions in PHP.

Is there a way to do that? I tried this code but it does nothing:

preg_replace("/\/(.+?)$/", '', $something_not_important);

Do you know where my mistake is?

Answer 1

Works perfectly fine for me...

<?php
$something_not_important = '442_38489_ext/index.php';
$something_changed = preg_replace("/\/(.+?)$/", '', $something_not_important);
var_dump($something_changed);

The output of above code is:

string(13) "442_38489_ext"

Maybe you did not assign the return value of the call to preg_replace() ?

Answer 2

You may use dirname for your concrete case, or use a regex like '~/[^/]*$~' :

$something_not_important = "/more_here/442_38489_ext/index.php";
$s2 = dirname($something_not_important);
echo $s2 . "\n";

$s3 = preg_replace("~/[^/]*$~", '', $something_not_important);
echo $s3;

See the PHP demo

The /[^/]*$ pattern matches / , then 0+ chars other than / up to the end of string ( $ ).

Also, do not forget to assign the value to a variable, or it will not get updated.