關于 WordPress 禁止多個人同時登錄一個用戶賬號，倡萌之前就推薦過 Prevent Concurrent Logins ，今天推薦的 Wp Single Login 也可以實現一樣的功能，不過 Wp Single Login 是通過 WP 3.6 新增的 Heartbeat API 來實現的。

后臺插件安裝界面搜索 Wp Single Login 即可在線安裝，或者在這里下載 Wp Single Login ，直接安裝啟用即可，不需要設置。

當然，如果你不想用插件，或者想自定義某些代碼，以下就是該插件的源代碼：

<?php

/*

Plugin name: WP Single Login

Plugin URI: http://magnigenie.com/wp-single-login/

Description: This plugin will automatically logout the already logged in user when a user with the same login details tries to login from different browser or different computer. This plugin needs zero configuration to run. Just install it if you want single login functionality on your site.

Version: 1.0

Author: Nirmal Ram

Author URI: http://magnigenie.com/about-me/

License: GPLv2 or later

License URI: http://www.gnu.org/licenses/gpl-2.0.html

*/

if( !class_exists( 'wp_single_login' ) ) {

class wp_single_login {

private $session_id;

function __construct() {

if ( ! session_id() )

session_start();

$this->session_id = session_id();

add_action( 'init', array( $this, 'wpsl_init' ) );

add_action( 'wp_login', array( $this, 'wpsl_login' ), 10, 2 );

add_filter('heartbeat_received', array( $this, 'wpsl_heartbeat_received' ), 10, 2);

add_filter('heartbeat_nopriv_received', array( $this, 'wpsl_heartbeat_received' ), 10, 2);

add_filter( 'login_message', array( $this, 'wpsl_loggedout_msg' ), 10 );

}

function wpsl_init() {

if( ! is_user_logged_in() )

return;

//enqueue the Heartbeat API

wp_enqueue_script('heartbeat');

wp_enqueue_script('jquery');

//load our Javascript in the footer

add_action("wp_footer", array( $this, 'wpsl_scripts' ) );

$user_sess_id = get_user_meta( get_current_user_id(), '_wpsl_hash', true );

if( $user_sess_id != $this->session_id ) {

wp_logout();

wp_redirect( site_url( 'wp-login.php?wpsl=loggedout' ) );

exit;

}

}

function wpsl_login( $user_login, $user ) {

update_user_meta( $user->ID, '_wpsl_hash', $this->session_id );

return;

}

function wpsl_loggedout_msg() {

if ( isset($_GET['wpsl']) && $_GET['wpsl'] == 'loggedout' ) {

$msg = __( "Your session has been terminated as you are logged in from another browser." ) ;

$message = '<p class="message">'.$msg.'</p><br />';

return $message;

}

}

function wpsl_heartbeat_received($response, $data) {

$user_sess_id = get_user_meta( get_current_user_id(), '_wpsl_hash', true );

if( $data['user_hash'] && $data['user_hash'] != $user_sess_id ){

$response['wpsl_response'] = 1;

wp_logout();

}

else

$response['wpsl_response'] = 0;

return $response;

}

function wpsl_scripts() { ?>

<script>

jQuery(document).ready(function() {

wp.heartbeat.interval( 'fast' );

//hook into heartbeat-send: and send the current session id to the server

jQuery(document).on('heartbeat-send', function(e, data) {

data['user_hash'] = '<?php echo $this->session_id; ?>'; //need some data to kick off AJAX call

});

//hook into heartbeat-tick: client looks for a 'server' var in the data array and logs it to console

jQuery(document).on( 'heartbeat-tick', function( e, data ) {

if( data['wpsl_response'] ){

alert( '<?php _e('Your session has been terminated as you are logged in from another browser.'); ?>' );

window.location.href='<?php echo site_url( 'wp-login.php?wpsl=loggedout' ); ?> ';

}

});

});

</script>

<?php

}

}

new wp_single_login();

}

以上就是本文章的內容，希望對大家有所幫助