<?php

// Call function with ID of wanted menu, for example 'main-menu'
function cleanmenu( $menuID ) {

  $menu = array();

  foreach ( wp_get_nav_menu_items( $menuID ) as $link ):

    $menu[ $linkki->ID ] = array(
      'title' => $link->title,
      'url' => $link->url,
      'is_children' => false,
      'has_children' => false,
      'childrens' => array()
    );

    if ( $link->menu_item_parent !== '0' ): // Launch if menu-item has parent item
      $menu[ $link->ID ][ 'is_children' ] = true;
      $menu[ $link->menu_item_parent ][ 'has_children' ] = true;
      array_push( $menu[ $link->menu_item_parent ]['childrens'], $link->ID );
    endif;

  endforeach;

  return $menu;

}

?>