PHP信箱驗證碼：保護您的使用者帳戶免受未經授權存取的威脅。

require 'path/to/PHPMailer/src/PHPMailer.php';

$mail = new PHPMailerPHPMailerPHPMailer();
$mail->isSMTP();
$mail->SMTPAuth = true;
$mail->SMTPSecure = 'ssl';
$mail->Host = 'smtp.example.com';
$mail->Port = 465;
$mail->Username = 'your_username';
$mail->Password = 'your_password';
$mail->CharSet = 'UTF-8';

function generateVerificationCode($length) {
    $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $code = '';
    $max = strlen($characters) - 1;
    for ($i = 0; $i < $length; $i++) {
        $code .= $characters[rand(0, $max)];
    }
    return $code;
}

$to = 'test@example.com'; // 接收验证码的邮箱地址
$subject = '验证码'; // 邮件主题
$verificationCode = generateVerificationCode(6); // 生成6位验证码

$body = '您的验证码是：' . $verificationCode; // 邮件内容

$mail->setFrom('noreply@example.com', 'Your Website'); // 邮件发送者的地址和姓名
$mail->addAddress($to); // 添加邮件接收者的地址

$mail->isHTML(false); // 设置邮件内容为纯文本格式

$mail->Subject = $subject;
$mail->Body    = $body;

if ($mail->send()) {
    echo '验证码已发送，请查收';
} else {
    echo '验证码发送失败，请稍后再试';
}