mail.php

<?php

require 'config.php';

if (!ini_get('date.timezone')) {
    date_default_timezone_set('GMT');
}
$msg = '';
function Validate($name, $phone, $email, $message) {
    global $msg;
    if ($name == '' or $phone == '' or $email == '' or $message == '') {
        $msg = 'Please fill all the fields.';

        return false;
    }
    foreach ($_POST as $value) {
        if (stripos($value, 'Content-Type:') !== false) {
            $msg = 'There was a problem with the information you entered.';

            return false;
        }
    }

    return true;
}

function ValidateEmail($mail, $email) {
    global $msg;
    if (!$mail->ValidateAddress($email)) {
        $msg = 'You must specify a valid email address.';

        return false;
    }

    return true;
}

if ($_SERVER['REQUEST_METHOD'] == 'POST') {
    $name = trim($_POST['name']);
    $phone = trim($_POST['phone']);
    $email = trim($_POST['email']);
    $message = trim($_POST['message']);
    $data = array();
    if (Validate($name, $phone, $email, $message)) {
        require_once 'inc/phpmailer.php';
        $mail = new PHPMailer();
        if (ValidateEmail($mail, $email)) {
            $email_body = '';
            $email_body = $email_body.'Name: '.$name.'<br>';
            $email_body = $email_body.'Phone: '.$phone.'<br>';
            $email_body = $email_body.'Email: '.$email.'<br>';
            $email_body = $email_body.'Message: '.$message.'<br>';

            $mail->isSMTP();
            $mail->Host = 'smtp.sendgrid.net';
            $mail->SMTPAuth = true;
            $mail->Username = SD_USERNAME;
            $mail->Password = SD_PASSWORD;
            $mail->SMTPSecure = 'tls';
            $mail->Port = 587;

            $mail->SetFrom($email, $name);
            $address = 'renaissance@jecrc.ac.in';
            $mail->AddAddress($address, 'Renaissance');
            $mail->Subject = $name.' | Renaissance Contact';
            $mail->MsgHTML($email_body);
            if (!$mail->Send()) {
                $msg = 'There was a problem sending the email.';
            }
        }
    }
    if ($msg != '') {
        $data['success'] = false;
        $data['error'] = $msg;
    } else {
        $data['success'] = true;
        $data['message'] = 'success';
    }

    echo json_encode($data);
} else {
    echo 'error';
}