我正在尝试使用访问存储在用户配置文件中的IDadd_user_meta 以及get_user_meta 函数返回ID，但当我打印出这些值时，会得到这个奇怪的值。我可以看到ID在里面，但我不太明白如何对它进行编码，只显示值，而不显示所有其他内容。[school_id] => Array ( [0] => a:1:{i:0;i:88;} )

How the data is being added

/*
* Create new custom post type post on new user registration
*/
add_action( \'user_register\', \'add_user_to_school_cpt\', 10, 1 );
function add_user_to_school_cpt( $user_id )
{
   // Get user info
   $user_info = get_userdata( $user_id );

   // Create a new post
   $school_post = array(
       \'post_title\'   => get_field(\'name\', \'user_\' . $user_id), 
       \'post_content\' => $user_info->description,
       \'post_type\'    => \'school\',
       \'post_status\'  => \'publish\',
       \'post_author\'  => $user_id,
   );

   // Insert the post into the database
   $school_id = wp_insert_post( $school_post );

   // Add the school ID as a meta data
   add_user_meta( $user_id, \'school_id\', [$school_id] );

   // Add school custom fields
   add_post_meta( $school_id, \'email\', $user_info->user_email );
   add_post_meta( $school_id, \'school_telephone\', get_field(\'telephone\', \'user_\' . $user_id) );
   add_post_meta( $school_id, \'school_city\', get_field(\'city\', \'user_\' . $user_id) );
   add_post_meta( $school_id, \'school_postcode\', get_field(\'postcode\', \'user_\' . $user_id) );
   add_post_meta( $school_id, \'school_address\', get_field(\'address\', \'user_\' . $user_id) );
} ```