woocommerce_get_items_key │ filter-hook │ WC 1.0

Usage

add_filter( 'woocommerce_get_items_key', 'wp_kama_woocommerce_get_items_key_filter', 10, 2 );

/**
 * Function for `woocommerce_get_items_key` filter-hook.
 * 
 * @param  $string 
 * @param  $item   
 *
 * @return 
 */
function wp_kama_woocommerce_get_items_key_filter( $string, $item ){

	// filter...
	return $string;
}

$string

-

$item

-

Where the hook is called

return apply_filters( 'woocommerce_get_items_key', '', $item );

Where the hook is used in WooCommerce