function cleanInput($input) {
 $search = array(
  \'@]*?>.*?@si\', // Strip out javascript
  \'@<[\\/\\!]*?[^<>]*?>@si\', // Strip out HTML tags
  \'@
]*?>.*?
@siU\', // Strip style tags properly
  \'@@\' // Strip multi-line comments
 );
  $output = preg_replace($search, \'\', $input);
  return $output;
 }
function sanitize($input) {
  if (is_array($input)) {
    foreach($input as $var=>$val) {
      $output[$var] = sanitize($val);
    }
  }
  else {
    if (get_magic_quotes_gpc()) {
      $input = stripslashes($input);
    }
    $input = cleanInput($input);
    $output = mysql_real_escape_string($input);
  }
  return $output;
}
// Usage:
$bad_string = \"Hi! It\'s a good day!\";
$good_string = sanitize($bad_string);
// $good_string returns \"Hi! It\\\'s a good day!\"
// Also use for getting POST/GET variables
$_POST = sanitize($_POST);
$_GET = sanitize($_GET);