WordPress自定义短码：Swiper滑块无法获取相册图片等问题求助

Hey there, let's tackle your three WordPress shortcode issues one by one—these are common pitfalls I’ve worked through before, so here’s what you need to do:

1. Fix get_post_gallery_images() returning an empty array #

The core problem here is that get_post_gallery_images() only looks for top-level [gallery] shortcodes directly in your post content. Since your [gallery] is nested inside [bs-slider], the function can’t find it. Plus, there are two other easy-to-miss issues in your code:

• Shortcode attributes are always passed as strings, so checking === true will never match your pagination="true" input.
• Swiper requires every slide to be wrapped in a <div class="swiper-slide"> element—your original code was missing this, so even if images loaded, the slider wouldn’t render correctly.

Here’s the fixed imgSlider function that parses nested galleries and fixes these issues:

public function imgSlider( $attr, $content ) { 
    global $post; 
    $a = shortcode_atts(array( 
        'pagination' => 'false', 
        'buttons' => 'false', 
        'scrollbar' => 'false' 
    ), $attr); 

    $images = array();
    // Extract nested [gallery] shortcode attributes
    if (preg_match('/\[gallery\s(.*?)\]/', $content, $matches)) {
        $gallery_attr = shortcode_parse_atts($matches[1]);
        // Grab image IDs from the gallery's 'ids' parameter
        if (!empty($gallery_attr['ids'])) {
            $image_ids = explode(',', $gallery_attr['ids']);
            foreach ($image_ids as $id) {
                // Use the size specified in the gallery shortcode (default to 'large')
                $size = !empty($gallery_attr['size']) ? $gallery_attr['size'] : 'large';
                $image_url = wp_get_attachment_image_url(trim($id), $size);
                if ($image_url) {
                    $images[] = $image_url;
                }
            }
        }
    }

    $slider = ''; 
    if( !empty($images) ){ 
        $slider = '<div class="swiper-container">'; 
        $slider .= '<div class="swiper-wrapper">'; 
        foreach( $images as $img ){ 
            // Add required swiper-slide wrapper
            $slider .= '<div class="swiper-slide"><img class="img-fluid w-100" src="'. esc_url($img) .'"></div>'; 
        } 
        $slider .= '</div>'; 
        // Check against string values since shortcode attrs are strings
        if( $a['pagination'] === 'true' ){ 
            $slider .= '<div class="swiper-pagination"></div>'; 
        } 
        if( $a['buttons'] === 'true' ){ 
            $slider .= '<div class="swiper-button-prev"></div>'; 
            $slider .= '<div class="swiper-button-next"></div>'; 
        } 
        $slider .= '</div>'; 
    } 
    return $slider; 
}

2. Remove default WordPress gallery shortcode #

To ensure WordPress doesn’t parse the default [gallery] shortcode (and interfere with your custom slider), add this to your plugin’s initialization (e.g., your main class constructor):

public function __construct() {
    // Unregister the default gallery shortcode
    remove_shortcode('gallery');
    // Register your custom slider shortcode
    add_shortcode('bs-slider', array($this, 'imgSlider'));
}

If you want your [bs-slider] to handle all instances of the default [gallery] shortcode too, add this line alongside the others:

add_shortcode('gallery', array($this, 'imgSlider'));

3. Remove auto-added <p> and <br> tags #

WordPress’s wpautop filter automatically inserts these tags around content, including shortcodes. Here are two reliable fixes:

Option 1: Fix globally for all shortcodes #

Add these filters to your plugin to reorder how wpautop and shortcodes are processed:

// Disable default wpautop order
remove_filter('the_content', 'wpautop');
// Run wpautop before shortcodes are parsed
add_filter('the_content', 'wpautop', 99);
// Remove p/br tags that wrap shortcodes
add_filter('the_content', 'shortcode_unautop', 100);

Option 2: Target only your bs-slider shortcode #

If you don’t want to affect other content, clean up the output specifically for your slider:

add_filter('do_shortcode_tag', function($output, $tag) {
    if ($tag === 'bs-slider') {
        // Remove empty p tags wrapping slider elements
        $output = preg_replace('#<p>\s*(</?div>)\s*</p>#', '$1', $output);
        // Remove stray br tags
        $output = preg_replace('#<br\s*/?>#', '', $output);
    }
    return $output;
}, 10, 2);

内容的提问来源于stack exchange，提问作者ussarin0