typecho控制标题字数用省略号代替方法的教程

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                        $this->widget('Widget_Contents_Post_Recent', 'pageSize=6')->to($recent);
                        if ($recent->have()) :
                            while ($recent->next()) :
                        ?>
                                <li><time><?php $recent->date('Y-m-d'); ?></time><a href="<?php $recent->permalink(); ?>"><?php $recent->title(20, '...'); ?></a></li>
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                        endif; ?>
                    </ul>