Detect if string begins by x digits number in php

Question

How can I rename file if it begins by 5 digits?

This is what I tried:

$filename = '156272_abc.png';
$string = PREG_REPLACE("/[^0-9]i5/", '', $filename);

But it doesn't work.

Could you please point me in the right direction?

Thanks.

Answer 1

I think what you want is this:

$filename = '156272_abc.png';
$replacement = preg_replace("/^(\d{5,}).*(\.[^.]+)$/", "$1$2", $filename);

This will match any filename beginning with five or more digits, and replace with just the leading digits, followed by the extension.