aklast/common/helpers/Email.php

<?php

namespace common\helpers;

use Yii;

class Email
{
    /**
     * @param string $email
     * @return bool|string
     */
    public static function sendAdminLoginCode(string $email)
    {
        $subject = 'Elken Login Code';
        $code = Tool::randomString(6);
        $message = sprintf('验证码：%s. 有效时长5分钟.', $code);

        $mailer = Yii::$app->mailer;
        $mailer->useFileTransport = false;
        $result = $mailer->compose()
            ->setFrom('eshop-noreply@elken.com')
            ->setTo($email)
            ->setSubject($subject)
            ->setHtmlBody($message)
            ->send();

        return !$result ? false : $code;
    }
}