我一直在尝试使用add\\u filter将一些项目添加到WordPress内容的中间。该代码成功地将广告代码添加到WordPress内容的顶部，但没有插入。

以下是我使用的代码：

add_filter(\'the_content\', \'bbtre_amazon_content_filter\');
function bbtre_amazon_content_filter($content){

if(is_singular(\'post\')){
    $count = explode(\'</p>\', $content);
    foreach($count as $i => $paragraph){
        $count = $i+1;
        }

    $content = explode(\'</p>\', $content);

    foreach( $content as $index => $paragraph){
        if(trim($paragraph)){
            $content["{$index}"] .= \'</p>\';
        }

        if($index == intval($count/2)){
            $ads = bbtre_the_amazon_items();
            $content["{$index}"] .= $ads;
        }
    }
}

$content = (is_array($content)) ? implode($content) : $content;

return $content;
}

bbtre\\u中的亚马逊项目（）；

function bbtre_the_amazon_items(){
include(get_stylesheet_directory() .\'/inc/reshare/templates/ads/amazon.items.php\');
}

模板页面内：

<div class="amazon-item-wrap"><?php echo bbtre_get_amazon_items_list(); ?></div>

请任何人帮我解决这个问题。

注意：当我使用

$content["{$index}"] .= \'<p>Hello World</p>\';

而不是：

$content["{$index}"] .= $ads;

function bbtre_amazon_content_filter( $content ) {
    if ( ! is_single() ) {
        return $content; // Return early if not single post
    }

    // Paragraphs array without the closing tag
    $paragraphs       = explode( \'</p>\', $content );
    // Number of paragraphs in $paragraphs
    $paragraphs_count = count( $paragraphs );
    // Middle index of $paragraphs
    $middle_index     = absint( floor( $paragraphs_count / 2 ) );
    // New content string
    $new_content      = \'\';

    for ( $i = 0; $i < $paragraphs_count; $i++ ) {
        if ( $i === $middle_index ) {
            // Add custom content in the middle of post contents
            $new_content .= bbtre_the_amazon_items();
        }
        // Append the missing closing p tag
        $new_content .= $paragraphs[ $i ] . \'</p>\';
    }
    return $new_content;
}
add_filter( \'the_content\', \'bbtre_amazon_content_filter\' );