WordPress is_tree Functions for Custom Post Types & Ancestors

November 2, 2012 11:21am

The is_tree function has been floating around for years, however it’s grown a bit outdated and doesn’t accommodate for custom post types, or for ancestors of a page. So right now the old is_tree function can tell if a Page is a child of another Page, but not if it’s a “grandchild” of a particular Page.

Here’s the update, which will do everything as promised:

function is_tree($pid) {      // $pid = The ID of the page we're looking for pages underneath

	global $post;         // load details about this page

	$cpid = get_the_ID();

	$parents = get_post_ancestors( $post->ID ); // get the ancestors

	$ancestorid = ($parents) ? $parents[count($parents)-1]: $post->ID;

	if(($post->post_parent==$pid||$cpid==$pid||$ancestorid==$pid))

    	return true;   // we're at the page or at a sub page

	else

        return false;  // we're elsewhere

};

Enjoy!

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