Ajax remote validate wordpress username and email

Question

Does anyone know how to validate wordpress username and email with jquery validation plugin?

I'm trying to check if username and email exists with validation's remote method.

And I notice wordpress has functions like username_exists and email_exists, is there a quick way to do the job?

Plz help~

Answer 1

You can use something like this on client side (the ajax URL does not have to be hardcoded, check note here: http://codex.wordpress.org/AJAX_in_Plugins#Ajax_on_the_Viewer-Facing_Side):

"user_email":{
        remote: {
            url: 'YOURSITE.COM/wp-admin/admin-ajax.php',
            type: "post",
            data: {
               'user_email': function() {
                    return $( "#user_email" ).val();
                },
               'action': 'check_user_email'

            }
        }
}

And this in functions.php:

add_action( 'wp_ajax_nopriv_check_user_email', 'check_user_email_callback' );
function check_user_email_callback() {
    global $wpdb; // this is how you get access to the database
    if(email_exists($_POST['user_email'])){
        echo json_encode('error.');
    }
    else{
        echo json_encode('true');
    }
    die();
}