WP_List_Util::filter( array $args = array(), string $operator = 'AND' )

Filters the list, based on a set of key => value arguments.

Description

Retrieves the objects from the list that match the given arguments. Key represents property name, and value represents property value.

If an object has more properties than those specified in arguments, that will not disqualify it. When using the ‘AND’ operator, any missing properties will disqualify it.

Parameters

$args

(array) (Optional) An array of key => value arguments to match against each object.

Default value: array()

$operator

(string) (Optional) The logical operation to perform. 'AND' means all elements from the array must match. 'OR' means only one element needs to match. 'NOT' means no elements may match.

Default value: 'AND'

Return

(array) Array of found values.

Source

File: wp-includes/class-wp-list-util.php

public function filter( $args = array(), $operator = 'AND' ) {
		if ( empty( $args ) ) {
			return $this->output;
		}

		$operator = strtoupper( $operator );

		if ( ! in_array( $operator, array( 'AND', 'OR', 'NOT' ), true ) ) {
			return array();
		}

		$count    = count( $args );
		$filtered = array();

		foreach ( $this->output as $key => $obj ) {
			$matched = 0;

			foreach ( $args as $m_key => $m_value ) {
				if ( is_array( $obj ) ) {
					// Treat object as an array.
					if ( array_key_exists( $m_key, $obj ) && ( $m_value == $obj[ $m_key ] ) ) {
						$matched++;
					}
				} elseif ( is_object( $obj ) ) {
					// Treat object as an object.
					if ( isset( $obj->{$m_key} ) && ( $m_value == $obj->{$m_key} ) ) {
						$matched++;
					}
				}
			}

			if ( ( 'AND' === $operator && $matched === $count )
				|| ( 'OR' === $operator && $matched > 0 )
				|| ( 'NOT' === $operator && 0 === $matched )
			) {
				$filtered[ $key ] = $obj;
			}
		}

		$this->output = $filtered;

		return $this->output;
	}

Changelog

Version Description
4.7.0 Introduced.

© 2003–2021 WordPress Foundation
Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/classes/wp_list_util/filter