I want to apply lazy load to only certain images. I found here ( Replace image attributes for lazyload plugin (data-src) ) a way to create the data-src attributes and replace the src attribute with the correct image. Right now my code applies the lazy load to all the images, and I just want to apply it to the images with the class lazy-load.
This is how my code looks right now
// Lazyload Converter
function add_lazyload($content) {
$content = mb_convert_encoding($content, 'HTML-ENTITIES', "UTF-8");
$dom = new DOMDocument();
@$dom->loadHTML($content);
$images = [];
foreach ($dom->getElementsByTagName('img') as $node) {
$images[] = $node;
}
foreach ($images as $node) {
$fallback = $node->cloneNode(true);
$oldsrc = $node->getAttribute('src');
$node->setAttribute('data-src', $oldsrc );
$newsrc = get_template_directory_uri() . '/assets/placeholders/squares.svg';
$node->setAttribute('src', $newsrc);
$oldsrcset = $node->getAttribute('srcset');
$node->setAttribute('data-srcset', $oldsrcset );
$newsrcset = '';
$node->setAttribute('srcset', $newsrcset);
$noscript = $dom->createElement('noscript', '');
$node->parentNode->insertBefore($noscript, $node);
$noscript->appendChild($fallback);
}
$newHtml = preg_replace('/^<!DOCTYPE.+?>/', '', str_replace( array('<html>', '</html>', '<body>', '</body>'), array('', '', '', ''), $dom->saveHTML()));
return $newHtml;
}
add_filter('the_content', 'add_lazyload');
add_filter('post_thumbnail_html', 'add_lazyload');
how can I get the element by class instead of using tag?