Php WordPress在滑块中发布摘录

我想创建一个滑块，但无法使文章摘录正常工作。标题和permalink正在运行，但摘录不会显示。。。这是我的密码：

// Args
                        $args = array(
                            'cat' => $categories,
                            'post_type' => 'post',
                            'posts_per_page' => $amount,
                        );
                        // Our incrementing counter, leave this set to 0
                        $counter = 0;
                        // Query the posts based off of the parameters in the $args variable
                        $bs_posts = new WP_Query( $args );
                        // Our calculated limit of how many posts we have to work with, don't change this
                        $bs_posts_limit = count( $bs_posts->posts ) - 1;
                        // How many posts to display in each slide of the SlideDeck
                        $per_page = !empty($this->options['per-slide']) ? $this->options['per-slide'] : '2';
                        // Add "active" class to 1st slider item
                        $j=1;   

        // Carousel/Slider Html
                echo    "$tab<div" . (!empty($this->options['id']) ? ' id="slider-' . trim($thesis->api->esc($this->options['id'])) . '"' : '') . ' class="carousel slide'. (!empty($this->options['c-type']) ? ' ' . trim($thesis->api->esc($this->options['c-type'])) : '') .''. (!empty($this->options['class']) ? ' ' . trim($thesis->api->esc($this->options['class'])) : '') . "\" data-ride=\"carousel\">\n".
                        "$tab<h2 class=\"text-shadow\">". stripslashes($this->options['intro']) ."</h2>\n".
                        "$tab<div class=\"carousel-inner\">\n";
                    ?> 
                    <?php foreach( $bs_posts->posts as $bs_post ): ?>               
                    <?php
                        // Variables
                        $slide_number = floor( $counter / $per_page ) + 1;
                        $slide_mod = $counter % $per_page;
                        $bs_post_ID = $bs_post->ID;
                        $bs_post_title = get_the_title( $bs_post_ID );
                        $bs_post_link = get_permalink( $bs_post_ID );
                        $bs_post_excerpt = get_the_excerpt( $bs_post_ID );
                    ?>
                        <?php if( $slide_mod == 0 ): ?>
                        <div class="item <?php if($j <= 1) {echo 'active';} ?>">  
                        <?php endif; ?>
                        <div class="single">
                        <?php if (has_post_thumbnail( $bs_post->ID )) the_post_thumbnail( 'thumbnail', array( 'title' => "#htmlcaption") ) ?>
                        <a href="<?php echo $bs_post_link; ?>"><?php echo $bs_post_title;?></a> 
                        <?php echo $bs_post_excerpt; ?>             
                        <a href="<?php echo $bs_post_link; ?>" class="btn btn-default btn-xs" style="float:right;">Read More</a>                
                        </div>
                        <?php if( $slide_mod == ( $per_page - 1 ) || $counter == $bs_posts_limit ): ?>
                        </div>

                    <?php endif; ?>

                    <?php $counter++; $j++;?>

                <?php endforeach; ?>
                <?
                echo    "$tab</div>\n".
                        "$tab</div>\n"; 
                ?>
        <?

//参数
$args=数组(
“cat”=>$categories，
“post_type”=>“post”，
“每页帖子数”=>$amount，
);
//我们的递增计数器，将此设置保留为0
$counter=0；
//根据$args变量中的参数查询帖子
$bs_posts=新的WP_查询（$args）；
//我们计算出的要处理多少个帖子的限制，不要改变这一点
$bs_posts\u limit=计数（$bs_posts->posts）-1；
//在幻灯片的每个幻灯片中显示多少篇文章
$per_page=！空（$this->options['per-slide']）$此->选项['per-slide']：'2'；
//将“活动”类添加到第一个滑块项
$j=1；
//转盘/滑块Html
echo“$tab在查看文档后，我发现get_the_extract（）没有post id参数。它必须在lop中使用


如果你想在循环之外获取摘录，你必须获取文章的全部内容，并自己将其截断。
谢谢你的帮助。我已经成功地将其运行了。再次感谢。