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cat_is_ancestor_of( int|object $cat1, int|object $cat2 )

Checks if a category is an ancestor of another category.

You can use either an ID or the category object for both parameters. If you use an integer, the category will be retrieved.

$cat1: (int|object) (Required) ID or object to check if this is the parent category.
$cat2: (int|object) (Required) The child category.

(bool) Whether $cat2 is child of $cat1.

The function evaluates if the second category is a child of the first category.
Any level of ancestry will return True.
Arguments should be either integer or objects; if arguments are string representations of integers and not true integers, cat_is_ancestor_of will return False.

function cat_is_ancestor_of( $cat1, $cat2 ) {
	return term_is_ancestor_of( $cat1, $cat2, 'category' );
}

Uses	Description
wp-includes/taxonomy.php: term_is_ancestor_of()	Check if a term is an ancestor of another term.

Version	Description
2.1.0	Introduced.

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Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/functions/cat_is_ancestor_of