How do I output a database option that is an array into a get_posts array?

Question

This must be fairly simple, but I'm puzzled. And I may be going about it backwards.

How do I output a database option that is an array into a get_posts array?

I have an option in the database that stores some post IDs in the array format `1234,5678' . I can retrieve and echo them with

$options = get_option( 'pu_theme_options' );
$newspostids = $options['pu_textbox'];
echo $newspostids;

so I know am getting the output `1234,5678'. The database "option" is just text, saved from a form field in theme options.

What I need to do is get the data from that option into a get_posts array so I can display the posts by ID.

What I need is for get_posts to function like this:

$news = get_posts( array( 
            'post_type' => 'post', 
            'post__in'=> array(1234,5678)
            ) );

And, obviously, this doesn't work, putting the variable directly into the array and expecting it to output `1234,5678' :

$news = get_posts( array( 
            'post_type' => 'post', 
            'post__in'=> array($newspostids)
            ) );

So how should this work?

Answer 1

You could use wp_parse_id_list() to sanitize your comma seperated list of post IDs. It's defined as:

function wp_parse_id_list( $list ) {
    if ( !is_array($list) )
        $list = preg_split('/[\s,]+/', $list);

    return array_unique(array_map('absint', $list));
}

where we can see that it returns unique array values as well.

Note that absint() is defined in core as abs( intval() ) and there's a difference in the max output of intval() for 32 and 64 bit systems according to the PHP docs.

Answer 2

get_posts doesn't have a post__in "variable", that's in wp_query, in get_posts (or get_pages) you would need to use include e.g.

$news  = get_posts(
 array(
  'post_type' => 'post',
  'include' => $newspostids,
 )
);

https://codex.wordpress.org/Function_Reference/get_posts