You can use a regex like this:
-\d+x\d+(\.\w+)$
The code you can use is:
$re = "/-\\d+x\\d+(\\.\\w+)$/";
$str = "http://website.dev/2014/05/my-file-name-here-710x557.png";
$subst="\1";
$result = preg_replace($re, $subst, $str, 1);
The idea is to match the resolution -NumbersXNumbers
using -\d+x\d+
(that we’ll get rid of it) and then capture the file extension by using (\.\w+)$
using capturing group. Check the substitution section above.
6
solved Remove the end of a string with a varying string length using PHP