只需添加跟踪用户名更改操作状态的元记录：

$user = wp_get_current_user();

$did_one_change = get_user_meta($user->ID, \'changed_username\', true);

if($did_one_change !== false)
  wp_die(\'You already changed your user name once!\');

wp_update_user(array(
  \'ID\'         => $user->ID, 
  \'first_name\' => $_POST[\'first_name\'],
  \'last_name\'  => $_POST[\'last_name\'],
));

// here add a meta entry that suggests the user has changed their name once
update_user_meta($user->ID, \'changed_username\', 1);