How to prevent character input except for some using preg_replace?

Question

PHP

There is a lot of material on the Internet about this, but I would like to know specific things for myself. How to prohibit all characters in the $title variable , except for ,.- , and insert - instead of prohibited ones - and so that - does not repeat more than once.
Input data: Cyrillic and Latin.

$title = preg_replace("/[^A-Za-z0-9]/"," ",$title);

Answer 1

You can find out here .
Test: here .