get_children - wp_get_attachment_image

Question

I explain my problem:

1. I create a post with an image
2. get_children - wp_get_attachment_image functions returns that image
3. I delete post image and add a different one
4. get_children - wp_get_attachment_image functions returns the two images (although the image that has been removed and is no longer in the post)

The code:

$args = array('post_parent'    => get_the_ID(),
              'post_type'      => 'attachment',
              'post_mime_type' => 'image'
         );

$images = get_children( $args );
if ($images) 
{
    foreach ($images as $image) 
    {
            echo wp_get_attachment_image($image->ID, 'full');
    }
}

Answer 1

You could Limit the output to 1 like this but this is not a solution, only a workaround:

    $args = array('post_parent'    => get_the_ID(),
          'numberposts' => 1, 
          'order'          =>  'ASC',
          'post_type'      => 'attachment',
          'post_mime_type' => 'image'
     );

$images = get_children( $args );
if ($images) 
{
    foreach ($images as $image) 
    {
        echo wp_get_attachment_image($image->ID, 'full');
    }
}

Have you the Premission to delete on your server?

Answer 2

The problem when you update / delete an image from a post or a page, WordPress doesn't change the value of the post_parent column of the attachment. So there is not a 'WordPress' way to exclude the images that are not actually inside the post. At least I haven't found one yet. The query will return all the images that was attached to this post no matter if they were deleted or not.

A solution to this problem is actually to grub the content of the post and search if the url of every image exists inside the post content. I am assuming that you run this script inside WordPress Loop since you are using get_the_ID().

Here is the code for that:

$args = array('post_parent'    => get_the_ID(),
              'post_type'      => 'attachment',
              'post_mime_type' => 'image'
        );

$images = get_children( $args );

// Store the content of the post
$content = get_the_content();

if ($images){

    foreach ($images as $image) {

        // Get the url of the specific image
        $url = wp_get_attachment_url($image->ID);

        /*
         * Get the position of the url inside the content.
         * If the url does not exist inside content
         * the strpos() returns false.
         */
        $position = strpos($content, $url);

        if ($position){

            echo wp_get_attachment_image($image->ID, 'full');

        }

    }

}