asterisk_hide.php

  $sublen) return join('', array_slice($t_string[0], $start, $sublen));
            return join('', array_slice($t_string[0], $start, $sublen));
        }
        else {
            $start = $start * 2;
            $sublen = $sublen * 2;
            $strlen = strlen($string);
            $tmpstr = '';
            for($i=0; $i<$strlen; $i++) {
                if ($i>=$start && $i<($start+$sublen)) {
                    if(ord(substr($string, $i, 1)) > 129) {
                        $tmpstr.= substr($string, $i, 2);
                    }
                    else {
                        $tmpstr.= substr($string, $i, 1);
                    }
                }
                if (ord(substr($string, $i, 1)) > 129) $i++;
            }
            //if (strlen($tmpstr) < $strlen) $tmpstr.= "...";
            return $tmpstr;
        }
    }

    $username = "森林生灵"; 
    echo cut_str($username, 1, 0) .'**'. cut_str($str, 1, -1); //输出结果为：森**灵