$re = '/([^\\\\?|\,|%])/';
$str = 'https://images.hicarbyecar.com/uploads/2016/10/Audi_R8_V10_%E2%80%93_Frontansicht,_13._Ma?rz_2011,_Wuppertal1.jpg
';
$subst = "$1?$2";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php