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get_all_category_ids() WP 2.0.0

Deprecated in 4.0.0. It is no longer supported and can be removed in future releases. Use get_terms() instead.

Retrieves all category IDs.

  • See: get_terms()

No Hooks.

Return

Object. List of all of the category IDs.

Usage

get_all_category_ids();

Code of get all category ids: wp-includes/deprecated.php VER 5.1.1

<?php
function get_all_category_ids() {
	_deprecated_function( __FUNCTION__, '4.0.0', 'get_terms()' );

	if ( ! $cat_ids = wp_cache_get( 'all_category_ids', 'category' ) ) {
		$cat_ids = get_terms( 'category', array('fields' => 'ids', 'get' => 'all') );
		wp_cache_add( 'all_category_ids', $cat_ids, 'category' );
	}

	return $cat_ids;
}