Array from form - Wordpress Metadata - php

Question

I got a custom post type, with a form for storing some data (name, url) to display in a template.
What I want to know is how can I store those values in an array?
An example of my code:
<? function files_metadata(){
global $post;
$custom = get_post_custom($post->ID);
$name = $custom["name"][0];
$url = $custom["url"][0];
echo '<input type="hidden" name="files_metadata" id="files_metadata" value="' .wp_create_nonce('files_m'). '" />'; ?>
<label>Name: </label><br/>
<input id="name" name="name" value="<?php echo $name; ?>" />
<label>Url: </label><br/>
<input id="url" name="url" value="<?php echo $url; ?>" />
<? function save_meta_files($post_id) {
if (!wp_verify_nonce($_POST['files_metadata'], 'files_m')) return $post_id;
if (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE) return $post_id;
update_post_meta($post_id, "name", $_POST["url"]);
update_post_meta($post_id, "url", $_POST["url"]);
}
add_action('save_post', 'save_meta_files'); ?>
To this I want to add something like...
$url = $custom["url"][0];
$url2 = $custom["url"][1];
$url3 = $custom["url"][2];
<input id="url" name="url[0]" value="<?php echo $url; ?>" />
<input id="url2" name="url[1]" value="<?php echo $url2; ?>" />
<input id="url3" name="url[2]" value="<?php echo $url3; ?>" />
update_post_meta($post_id, "url", $_POST["url"][0]);
update_post_meta($post_id, "url2", $_POST["url"][1]);
update_post_meta($post_id, "url3", $_POST["url"][2]);
...but that actually works...

Answer 1

A passed array will be serialized into a string: http://codex.wordpress.org/Function_Reference/update_post_meta
update_post_meta(
$post_id,
'files_metadata',
array(
'name1' => $_POST['name1'],
'url1' => $_POST['url1']
'name2' => $_POST['name2'],
'url2' => $_POST['url2']
)
);