WordPress媒体库访问PHP

Question

Im trying to find a way to pull random images from either a post or wordpress's built in image library. Im not sure how to query image uris from a post or the media library - is there a tag or method that I can adopt? Should I just write something in PHP to manually query the wordpress database? If so what is the most efficient way to return image urls?

PS I would have posted this on Wordpress Stack but it seemed more like a technical question than a wordpress-specific question so I brought here instead. Wordpress stack questions have a bad habit of not getting answered.

Answer 1

Wordpress has built-in functions to access the array on images attached to a post. I found this function on the web, and it might be just what you're looking for. It fetches the images attached to a post, sorts them randomly, and returns the URL of the first one:

function random_image_url($size=large) {

    global $post;
    if ( $images = get_posts(array(
        'post_parent' => get_the_ID(),
        'post_type' => 'attachment',
        'numberposts' => 1,
        'orderby' => 'rand',
        'post_mime_type' => 'image',))) {

        foreach( $images as $image ) {
            $attachmenturl=wp_get_attachment_image_src($image->ID, $size);
            $attachmenturl=$attachmenturl[0];
            echo ''.$attachmenturl.'';
        }

    }  else {
        echo '' . get_bloginfo ( 'stylesheet_directory' ) . '/img/no-attachment.gif';
    }
}

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