Question

I have a hard time getting around regular expressions and I’m trying to remove the last forward slash in a string :

$public_url = "https://api.mongohq.com/";

What I intend is remove the last forward slash and replace it with something else. I figured I could use preg_replace but I cannot find the right pattern for doing it.

Answer 1

You can use a negative lookafter-expression:

<?php
$public_url = "https://api.mongohq.com/";
$replace = "foobar";

echo preg_replace("~\/(?!.*\/)~", $replace, $public_url);
?>

Output:
https://api.mongohq.comfoobar

Update:
Use the following regex to avoid problems with characters behind the last slash:

echo preg_replace("~\/(?!.*\/)(.*)~", $replace, $public_url);

All characters behind the last slash are replaced, too. Thanks to knittl!