Try it with the fields parameter:
http://codex.ww.wp.xz.cn/Function_Reference/WP_Query#Return_Fields_Parameter
Example:
<?php
// preserve the original query
global $query_string;
$the_query = new WP_Query( $query_string . '&fields=ids' );
if(isset($the_query->posts) && !empty($the_query->posts)){
foreach((array) $the_query->posts as $id) {
echo $id;
}
}
?>
If you need the ids from a specific query you can also use get_posts:
<?php
// get 10 recent post IDs from category 1
$the_query = get_posts( 'cat=1&posts_per_page=10&fields=ids' );
if($the_query){
foreach($the_query as $id) {
echo $id;
}
}
?>
keesiemeijer, thanks for the quick reply!
This is exactly what I needed.
But now I have another question – what are possible values of “fields” option?
In docs it is:
‘ids’ – Return an array of post IDs.
‘id=>parent’ – Return an associative array [ parent => ID, … ].
any other value or empty (default): return an array of post objects
I don’t understand the second and third options – which keys/values are supported and why are they reversed – id=>parent then parent => ID?
And “any other value or empty” – value of what?
The second option will return all parent (page) ID’s:
$args = array('fields' => 'id=>post_status');
$the_query = get_posts( $args );
// $the_query returns all parent post IDs
All other values will return full post objects. Only ‘ids’ and ‘id=>parent’ is supported for now. the output for the parent post IDs is an array like:
[posts] => Array
(
[0] => stdClass Object
(
[ID] => 25
[post_parent] => 21
)
[1] => stdClass Object
(
[ID] => 32
[post_parent] => 0
)
)
I understood. Thank you very much!
You’re welcome. I’m glad you’ve got it resolved 🙂
