Notes

<?php

use PHPMailerPHPMailerPHPMailer;
use PHPMailerPHPMailerSMTP;
use PHPMailerPHPMailerException;

require '../vendors/phpmailer/src/Exception.php';
require '../vendors/phpmailer/src/PHPMailer.php';
require '../vendors/phpmailer/src/SMTP.php';

if($_SERVER["REQUEST_METHOD"] == "POST") {
// Sender Data
$senderName = trim(strip_tags($_POST["name"]));
$senderEmail = filter_var(trim(strip_tags($_POST["email"])), FILTER_SANITIZE_EMAIL);
$senderSubject = trim(strip_tags($_POST["subject"]));
$senderMessage = trim(htmlentities($_POST["message"]));

if(empty($senderName) || empty($senderEmail) || empty($senderSubject) || empty($senderMessage)) {
// Set a 400 (bad request) response code and exit
http_response_code(400);
echo "Please complete the form and try again!";
exit;
} else {
if(!filter_var($senderEmail, FILTER_VALIDATE_EMAIL)) {
// Set a 400 (bad request) response code and exit
http_response_code(400);
echo "Invalid email format!";
exit;
}
}

$mail = new PHPMailer(true);

try {
//Server settings
$mail->isSMTP(); // Send using SMTP
$mail->Host = 'smtp1.example.com'; // Set the SMTP server to send through
$mail->SMTPAuth = true; // Enable SMTP authentication
$mail->Username = '[email protected]'; // SMTP username
$mail->Password = 'secret'; // SMTP password
$mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS; // Enable TLS encryption; `PHPMailer::ENCRYPTION_SMTPS` also accepted
$mail->Port = 587; // TCP port to connect to

//Recipients
$mail->setFrom($senderEmail, $senderName);
$mail->addAddress('[email protected]', 'Your Name'); // Add a recipient
$mail->addReplyTo($senderEmail, $senderName);

// Content
$mail->isHTML(true); // Set email format to HTML
$mail->Subject = $senderSubject;
$mail->Body = "<b>Name</b>: $senderName<br><b>Email</b>: $senderEmail<br><br><b>Message</b>: $senderMessage";
$mail->AltBody = "Name: $senderNamenEmail: $senderEmailnnMessage: $senderMessage";

$mail->send();
echo 'Your message has been sent!';
} catch (Exception $e) {
http_response_code(400);
echo "Mailer Error: {$mail->ErrorInfo}";
}

} else {
// Not a POST request, set a 403 (forbidden) response code
http_response_code(403);
}

?>