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get_all_category_ids() WP 2.0.0

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

Retrieves all category IDs.

No Hooks.

Return

Int[]. List of all of the category IDs.

Usage

get_all_category_ids();

Notes

  • See: get_terms()

Changelog

Since 2.0.0 Introduced.
Deprecated Since 4.0.0 Use get_terms()

Code of get_all_category_ids() WP 5.7

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

	$cat_ids = get_terms(
		array(
			'taxonomy' => 'category',
			'fields'   => 'ids',
			'get'      => 'all',
		)
	);

	return $cat_ids;
}