WordPress Restricts Allowed Email Types for Registration (Email Blacklist/Whitelist)

Nowadays, more and more people are using WordPress to buildResource Download Siteor foreign trade websites, many of which have user registration enabled. If you check the Admin Dashboard user list, you'll find many accounts registered in bulk by bots, with email addresses from uncommon domain mailboxes. We can use the following two methods to simply restrict the email service providers allowed during WordPress registration.

Email Whitelist for Registration

For domestic users, it's recommended to use an email registration whitelist, because your main users are Chinese, and there are rarely registrations from users of those obscure domain mailboxes. We can allow registration only from common email services.

Usage Method: Copy the code below and paste it into the website theme's functions.php file.

/*
* WordPress注册邮箱白名单
* https://blog.naibabiji.com/skill/mail-registration-restrictions.html ‎
*/
function is_valid_email_domain($login, $email, $errors ){
$valid_email_domains = array("gmail.com","qq.com");// 允许注册的邮箱信息
$valid = false;
foreach( $valid_email_domains as $d ){
$d_length = strlen( $d );
$current_email_domain = strtolower( substr( $email, -($d_length), $d_length));
if( $current_email_domain == strtolower($d) ){
$valid = true;
break;
}
}
// if invalid, return error message
if( $valid === false ){
$errors->add('domain_whitelist_error',__( '<strong>ERROR</strong>: 本站只支持gmail和QQ邮箱注册。' ));
}
}
add_action('register_post', 'is_valid_email_domain',10,3 );

Registration Email Blacklist

If you have a foreign trade website, you will encounter many foreign users registering. They may use domain email addresses. You can check the backend user registration records to determine which domain email addresses are spam, and directly block registration from that domain.

At this point, you can use the Ban Hammer plugin, which makes it very convenient to set up a domain blacklist.

Download Link

In addition to email whitelists and blacklists, we can also add a simple registration verification to the website registration process to prevent bots from bulk registering. For example, to register for Naibabiji, you need to answer a question first to pass.