PHP Preg (regex) extracting last value from a string? not as simple as I thought

Question

I'm trying to use PHP preg to extract the integer at the end of the string below, in the example its "4", but could be any number coming after "INBOX/", also the "[email protected]" is a variable so it could be any address

STRING I'M EXTRACTING FROM:

/m/[email protected]/folder/INBOX/4

/STRING

I've been going in circles with this, I guess I don't really understand how to do this and the regex examples I am finding in my searches just don't seem to address something like this, I would greatly appreciate any help..

ps. If anyone knows of a good regex software for building queries like this (for extraction) I would appreciate letting me know as I have spent countless hours lately with regex and still haven't found a software that seems to help in this.. thanks

Answer 1

Use:

#/([^/]*)$#

preg_match('#/([^/]*)$#', $str, $matches);

We first check for a slash. Then the capturing group is zero or more non-slash characters. Then, the end of the string. $matches[1] holds the result.

Answer 2

Why not simply match \d+$ - this will match any trailing number.

if (preg_match('/\d+$/', $subject, $match)) {
    $result = $match[0];
} else {
    $result = "";
}

If you want to match anything (even it it's not a number) after the last slash, just use [^/]+$ instead:

preg_match('#[^/]+$#', $subject, $match)