WordPress/PHP get list of all links in primary navigation

I am trying to create a list of all links in primary navigation on my WordPress site. I am trying to output the link as URL: in a script tag using a foreach loop.

I am stuck trying to list of of the navitems links using $navItem->url in my foreach loop. It doesn’t return anything / false.

Instead of $locations[$menuLocations] I have tried simply just write primary menu name as well: $locations[‘primary’] but no luck so far.

function get_nav_menu_items_by_location( $location, $args = [] ) {
    $html = '<script type="application/ld+json" alt="hejtest">';

    // Get all locations
    $menuLocations = get_nav_menu_locations();
 
    // Get object id by location
    $object = wp_get_nav_menu_object( $locations[$menuLocations] );
 
    // Get menu items by menu name
    $menu_items = wp_get_nav_menu_items($object);
    
foreach ( $menu_items as $navItem ) {
    
    $html .= '"url":"' . $navItem->url . '"';
}
    $html .= "</script>";

    echo $html;
}
add_action('wp_head', 'get_nav_menu_items_by_location');

Answer

Well… I did a refactor of your code and it’s works 😉

Try with this way:

function get_nav_items() {

   $menu_slug_to_retrieve = 'main'; // This can be main, primary, what ever...
   $locations             = get_nav_menu_locations();
   $menu                  = wp_get_nav_menu_object( $locations[ $menu_slug_to_retrieve ] );
   $menu_items            = wp_get_nav_menu_items( $menu->term_id );
   $menu_items_json       = array(); // Prepare the array to convert to json

   // Loop it
   if ( $menu_items ) {

      foreach ( $menu_items as $item ) {
          $menu_items_json[] = array( 'url' => $item->url );
      }

      $html = sprintf(
          '<script type="application/ld+json" id="custom-json">%s</script>',
          json_encode( $menu_items_json )
      );

      echo $html;
   }
 }
 add_action( 'wp_head', 'get_nav_items' );

Regards!