文字が省略されない　makeShorterText

マルチバイト環境では、
長い質問項目が、そのまま表示され、質問項目が省略されないです。

##
#### ----- OPEN ---------------
#

inc/Utils.php

#
##--- Find --------------------
#

    public static function makeShorterText($str, $char)
    {
        $str = PMF_String::preg_replace('/\s+/', ' ', $str);
        $arrStr = explode(' ', $str);
        $shortStr = '';
        $num = count($arrStr);

        if ($num > $char) {
            for ($j = 0; $j <= $char; $j++) {
                $shortStr .= $arrStr[$j].' ';
            }
            $shortStr .= '...';
        } else {
            $shortStr = $str;
        }
        return $shortStr;
    }
#
### ---- Replace With --------------
#

    public static function makeShorterText($str, $char)
    {
        $str = PMF_String::preg_replace('/\s+/', ' ', $str);
/**
        $arrStr = explode(' ', $str);
        $shortStr = '';
        $num = count($arrStr);

        if ($num > $char) {
            for ($j = 0; $j <= $char; $j++) {
                $shortStr .= $arrStr[$j].' ';
            }
            $shortStr .= '...';
        } else {
            $shortStr = $str;
        }
***/
  $char = ($char * 6 ); // 6 is your Liking, 5..8 is best
        $shortStr = '';
  $num = mb_strlen($str);
  if ($num > $char) {
   $shortStr = mb_substr($str,0,$char);
   $shortStr .= '...';
        } else {
            $shortStr = $str;
        }
        return $shortStr;
    }