PHP filter_var() function allowing more than one minus in integer numbers

Question

I am trying to filter integers using filter_var(), but in this case:

echo filter_var('-3-6-5', FILTER_SANITIZE_NUMBER_INT); // Output: -3-6-5

Instead of -3-6-5 i expect to get -365.

Someone know how to solve this or a regex that do this?

Thanks for any help!

Answer 1

echo preg_replace('~^[^-\d]|(?<!^)\D~', '', '-3-6-5'); // -365

It will remove anything that is not a digit, keeping - sign in the beginning of the string