PHP：ThinkPHP使用PHPMailer发送html邮件

composer require phpmailer/phpmailer

<?php
// +----------------------------------------------------------------------
// | 邮件系统配置
// +----------------------------------------------------------------------
return [
    'MAIL_HOST'      => 'smtp.163.com',
    'MAIL_PORT'      => 465,
    'MAIL_USERNAME'  => 'xxx@163.com',
    'MAIL_PASSWORD'  => 'xxxxxx',
    'MAIL_FROM_NAME' => '山中无老虎',
];

<?php
namespace app\service;
use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\SMTP;
class MailService
{
    public static function send($subject, $body, array $address_list = [])
    {
        $mail = new PHPMailer(true);
        //服务器配置
        $mail->CharSet   = "UTF-8";   //设定邮件编码
        $mail->SMTPDebug = SMTP::DEBUG_OFF; // 调试模式输出
        $mail->isSMTP();                 // 使用SMTP
        // SMTP服务器
        $mail->Host = config('mail.MAIL_HOST');
        // 服务器端口 25 或者465 具体要看邮箱服务器支持
        $mail->Port       = config('mail.MAIL_PORT');
        $mail->SMTPAuth   = true;  // 允许 SMTP 认证
        $mail->Username   = config('mail.MAIL_USERNAME');  // SMTP 用户名  即邮箱的用户名
        $mail->Password   = config('mail.MAIL_PASSWORD');  // SMTP 密码  部分邮箱是授权码(例如163邮箱)
        $mail->SMTPSecure = 'ssl';  // 允许 TLS 或者ssl协议
        //发件人
        $mail->setFrom(config('mail.MAIL_USERNAME'), config('mail.MAIL_FROM_NAME'));
        // 收件人
        foreach ($address_list as $address) {
            $mail->addAddress($address);
        }
        //Content
        $mail->isHTML(true);                                  // 是否以HTML文档格式发送  发送后客户端可直接显示对应HTML内容
        $mail->Subject = $subject;
        $mail->Body    = $body;
        $mail->send();
    }
}

<?php
require_once __DIR__ . '/../../vendor/autoload.php';
((new \think\App())->http)->run();
use app\service\MailService;
use PHPUnit\Framework\TestCase;
class MailServiceTest extends TestCase
{
    /**
     * @doesNotPerformAssertions
     */
    public function testSend()
    {
        MailService::send('标题', '内容', ['xxx@qq.com']);
    }
}