Category names in menu

Hi there,

I’m trying to realize a menu with five randomly picked posts incl. the categories but I don’t quite know how to do it.

This is what I have so far, included in the header.php:

<li><a href="#">Stöbern</a>
		<ul>

    		<?php
        	$lastposts = get_posts('numberposts=5&orderby=rand');
        	foreach($lastposts as $post) :
        	setup_postdata($post);
		global $post;
		$categories = get_the_category($post->ID);
		var_dump($categories);
		?>

        	<li<?php if ( $post->ID == $wp_query->post->ID ) { echo ' class="current"'; } else {} ?>>

            	<a href="<?php the_permalink() ?>"><?php the_title(); ?> von <?php echo the_category('name')->name; ?>
</a>

        	</li>

   	 	<?php endforeach; ?>

		</ul>

            	</li>

Can anyone help me with that please?