WordPress at a glance
function is not described

WP_Widget_Search::update() public WP 2.8.0

Handles updating settings for the current Search widget instance.

{} It's a method of the class: WP_Widget_Search{}

No Hooks.

Return

Array. Updated settings.

Usage

$WP_Widget_Search = new WP_Widget_Search();
$WP_Widget_Search->update( $new_instance, $old_instance );
$new_instance(array) (required)
New settings for this instance as input by the user via WP_Widget::form().
$old_instance(array) (required)
Old settings for this instance.

Changelog

Since 2.8.0 Introduced.

Code of WP_Widget_Search::update() WP 5.7.2

<?php
public function update( $new_instance, $old_instance ) {
	$instance          = $old_instance;
	$new_instance      = wp_parse_args( (array) $new_instance, array( 'title' => '' ) );
	$instance['title'] = sanitize_text_field( $new_instance['title'] );
	return $instance;
}