get_post_ancestors( int|WP_Post $post )
Retrieve ancestors of a post.
Description Description
Parameters Parameters
- $post
-
(int|WP_Post) (Required) Post ID or post object.
Return Return
(array) Ancestor IDs or empty array if none are found.
Source Source
File: wp-includes/post.php
function get_post_ancestors( $post ) {
$post = get_post( $post );
if ( ! $post || empty( $post->post_parent ) || $post->post_parent == $post->ID ) {
return array();
}
$ancestors = array();
$id = $post->post_parent;
$ancestors[] = $id;
while ( $ancestor = get_post( $id ) ) {
// Loop detection: If the ancestor has been seen before, break.
if ( empty( $ancestor->post_parent ) || ( $ancestor->post_parent == $post->ID ) || in_array( $ancestor->post_parent, $ancestors ) ) {
break;
}
$id = $ancestor->post_parent;
$ancestors[] = $id;
}
return $ancestors;
}
Expand full source code Collapse full source code View on Trac
Changelog Changelog
| Version | Description |
|---|---|
| 2.5.0 | Introduced. |
User Contributed Notes User Contributed Notes
You must log in before being able to contribute a note or feedback.
Get Ancestors Page Slug
This example returns the highest page
{slug}in a tree and uses it as a Body_Class, so the parent and all children will have the same Body Class!This example for a twenty eleven child theme in the
header.phpfile</head> <?php /* Get the Page Slug to Use as a Body Class, this will only return a value on pages! */ $class = ''; /* is it a page */ if( is_page() ) { global $post; /* Get an array of Ancestors and Parents if they exist */ $parents = get_post_ancestors( $post->ID ); /* Get the top Level page->ID count base 1, array base 0 so -1 */ $id = ($parents) ? $parents[count($parents)-1]: $post->ID; /* Get the parent and set the $class with the page slug (post_name) */ $parent = get_post( $id ); $class = $parent->post_name; } ?> <body <?php body_class( $class ); ?>>Expand full source codeCollapse full source code
Get Ancestors Post Meta
If we did not want to use the page slug, we could use a custom field eg:
body_class, on the top level page and set the class in the post meta.</head> <?php $class = ''; if( is_page() ) { global $post; $parents = get_post_ancestors( $post->ID ); $id = ($parents) ? $parents[count($parents)-1]: $post->ID; $class = get_post_meta( $id, 'body_class', true ); } ?> <body <?php body_class( $class ); ?>>Expand full source codeCollapse full source code
Get Ancestors Page Thumbnail
Get the top level page thumbnail and display it!
<?php global $post; $parents = get_post_ancestors( $post->ID ); /* Get the ID of the 'top most' Page if not return current page ID */ $id = ($parents) ? $parents[count($parents)-1]: $post->ID; if(has_post_thumbnail( $id )) { get_the_post_thumbnail( $id, 'thumbnail'); } ?>