Remove non-utf8 characters from string

Function to remove any bad formatted bytes.
function remove_bs2($string) {
  $str_array = str_split($string);
  $new_str = '';
  foreach ($str_array as $char) {
    $char_no = ord($char);
    if ($char_no == 163) {
      $new_str .= $char;
      continue;
    } // keep £ 
    if ($char_no > 31 && $char_no < 127) {
      $new_str .= $char;
    }
  }
  return $new_str;
}

 

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