Question

I have a php script validation that looks for some special chars and deletes them. The script works fine but if I put anything between two $ it is deleted as well. So if put in

Supercool$$$$%%email%%@%SP***AM.com; => [e-mail]

but if I input

Supercool$$email$$%%@%SP**AM.com => [e-mail]

Whenever I put regular chars between $’s they are delete as well. Here is the PHP script that I use to check for special chars in the inputed email:

<?php

$bademail = "MAXCOOL$$ES$$%%T%%@%SP***AM.com";

function specialcharsreg ($email){
    $regex = "/[*?$!%$&#]/";
    $validemail = preg_replace($regex, "", $email);
    echo "\n=====================================\n".$email." -> ".$validemail."\n=====================================\n\n";
}
specialcharsreg($bademail);
?>

Answer 1

The expression does not replace that.

You are just not quoting your string properly and $variables are getting interpolated.

Your (double quotes):

$bademail = "MAXCOOL$$ES$$%%T%%@%SP***AM.com";

Should be (variables are not interpolated when using single quotes):

$bademail = 'MAXCOOL$$ES$$%%T%%@%SP***AM.com';

Or you can escape the $s with backslashes:

$bademail = "MAXCOOL\$\$ES\$\$%%T%%@%SP***AM.com";