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Question

I am trying to create a list of PDFs (newsletters created each month). I have created a custom post type named 'newsletters' and restricted it to only supporting a 'title'.

I have then used the advanced custom fields plugin to add a file upload button to this post type. Therefore each post has a title and a button to upload the pdf.

I have then written the below function to output the list of attachments.

function list_newsletters(){

    $args = array( 'post_type' => 'newsletters' );
    $loop = new WP_Query( $args );
    while ( $loop->have_posts() ) : $loop->the_post();
        $permalink = get_permalink();
        $title = get_the_title();
        $id = get_the_ID();
        $attachment = wp_get_attachment_url($id);
        echo '<li><a href="'.$attachment.'">'.$title.'</li>';
    endwhile;

}

However the wp_get_attachment_url($id) doesn't seem to work. I think this is because I am supposed to be supplying the attachment ID rather than the post ID. I have looked around online and cannot find a clear way of finding the attachment ID for a specific post.

Just to clarify each post will only contain one attached file.

Thank you in advance

Answer 1

This example taken from the get_posts() Codex page

$attachments = get_posts(array( 
    'post_type' => 'attachment',
    'numberposts' => -1,
    'post_status' =>'any',
    'post_parent' => $post->ID
));

if ($attachments) {
    foreach ( $attachments as $attachment ) {
        echo apply_filters( 'the_title' , $attachment->post_title );
        the_attachment_link( $attachment->ID , false );
    }
}