remove special characters from string except @ in php code example

Example 1: php remove last character from string

$hell = substr('hello', 0, -1);

Example 2: determine special characters in php

<?php

$string = 'foo';

if (preg_match('/[\'^£$%&*()}{@#~?><>,|=_+¬-]/', $string))
{
    // one or more of the 'special characters' found in $string
}