php提交到邮箱

<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $to = "recipient@example.com";
    $subject = "Subject of the Email";
    $message = "Hello, this is a test email.";
    $headers = "From: sender@example.com";

    if (mail($to, $subject, $message, $headers)) {
        echo "Email successfully sent.";
    } else {
        echo "Email delivery failed.";
    }
}
?>

<?php
require 'path/to/PHPMailer/src/PHPMailer.php';
require 'path/to/PHPMailer/src/SMTP.php';
require 'path/to/PHPMailer/src/Exception.php';

use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception;
use PHPMailer\PHPMailer\SMTP;

$mail = new PHPMailer(true);

try {
    // Server settings
    $mail->SMTPDebug = SMTP::DEBUG_SERVER;
    $mail->isSMTP();
    $mail->Host       = 'smtp.example.com';
    $mail->SMTPAuth   = true;
    $mail->Username   = 'smtp_username';
    $mail->Password   = 'smtp_password';
    $mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
    $mail->Port       = 587;

    // Recipients
    $mail->setFrom('sender@example.com', 'Mailer');
    $mail->addAddress('recipient@example.com', 'Joe User');     // Add a recipient

    // Content
    $mail->isHTML(true);                                  // Set email format to HTML
    $mail->Subject = 'Subject of the Email';
    $mail->Body    = 'Hello, this is a test email.';
    $mail->AltBody = 'This is the body in plain text for non-HTML mail clients';

    $mail->send();
    echo 'Message has been sent';
} catch (Exception $e) {
    echo "Message could not be sent. Mailer Error: {$mail->ErrorInfo}";
}
?>