WordPress/wp-admin/network/user-new.php

<?php
/**
 * Add Site Administration Screen
 *
 * @package WordPress
 * @subpackage Multisite
 * @since 3.1.0
 */

/** Load WordPress Administration Bootstrap */
require_once( './admin.php' );

if ( ! is_multisite() )
	wp_die( __( 'Multisite support is not enabled.' ) );

if ( ! current_user_can('create_users') )
	wp_die(__('You do not have sufficient permissions to add users to this network.'));

if ( isset($_REQUEST['action']) && 'add-user' == $_REQUEST['action'] ) {
	check_admin_referer( 'add-user', '_wpnonce_add-user' );
	if ( ! current_user_can( 'manage_network_users' ) )
		wp_die( __( 'You do not have permission to access this page.' ) );

	if ( is_array( $_POST['user'] ) == false )
		wp_die( __( 'Cannot create an empty user.' ) );
	$user = $_POST['user'];
	if ( empty($user['username']) && empty($user['email']) )
		wp_die( __( 'Missing username and email.' ) );
	elseif ( empty($user['username']) )
		wp_die( __( 'Missing username.' ) );
	elseif ( empty($user['email']) )
		wp_die( __( 'Missing email.' ) );

	$password = wp_generate_password( 12, false);
	$user_id = wpmu_create_user( esc_html( strtolower( $user['username'] ) ), $password, esc_html( $user['email'] ) );

	if ( false == $user_id )
 		wp_die( __( 'Duplicated username or email address.' ) );
	else
		wp_new_user_notification( $user_id, $password );
		
	wp_redirect( add_query_arg( array('update' => 'added'), 'user-new.php' ) );
	exit;
}

if ( isset($_GET['update']) ) {
	$messages = array();
	if ( 'added' == $_GET['update'] )
		$messages[] = __('User added.');
}

$title = __('Add New User');
$parent_file = 'users.php';

require('../admin-header.php'); ?>

<div class="wrap">
<?php screen_icon(); ?>
<h2 id="add-new-user"><?php _e('Add New User') ?></h2>
<?php
if ( ! empty( $messages ) ) {
	foreach ( $messages as $msg )
		echo '<div id="message" class="updated"><p>' . $msg . '</p></div>';
} ?>
	<form action="<?php echo network_admin_url('user-new.php?action=add-user'); ?>" method="post">	
	<table class="form-table">
		<tr class="form-field form-required">
			<th scope="row"><?php _e( 'Username' ) ?></th>
			<td><input type="text" class="regular-text" name="user[username]" /></td>
		</tr>
		<tr class="form-field form-required">
			<th scope="row"><?php _e( 'Email' ) ?></th>
			<td><input type="text" class="regular-text" name="user[email]" /></td>
		</tr>
		<tr class="form-field">
			<td colspan="2"><?php _e( 'Username and password will be mailed to the above email address.' ) ?></td>
		</tr>
	</table>
	<p class="submit">
		<?php wp_nonce_field( 'add-user', '_wpnonce_add-user' ) ?>
		<?php submit_button( __('Add User'), 'primary', 'add-user' ); ?>
	</form>
</div>
<?php
require('../admin-footer.php');
?>