有没有更好的方法来解决这个phpmailer问题

Question

当我在表单中输入电子邮件a@gmail.com时。在gmail中显示（表格：b@gmail.com）。每当有人输入电子邮件时，它都不会在gmail中显示其电子邮件，而只会显示b @ mail形式。为什么?????我的代码有问题吗

<?php
$result = "";
if (isset($_POST['submit'])) {
    require 'phpmailer/PHPMailerAutoload.php';
    $mail = new PHPMailer;
    $mail->isSMTP();
    $mail->Host = 'smtp.gmail.com';
    $mail->Port = 587;
    $mail->SMTPAuth = true;
    $mail->SMTPSecure = 'tls';

    $mail->Username = 'b@gmail.com';
    $mail->Password = '';  // i provided my password but i cann't show you guys                 

    $mail->setFrom($_POST['email'], $_POST['name']);
    $mail->addAddress('b@gmail.com');
    //$mail->addReplyTo($_POST['email'],$_POST['name']);         
    $mail->isHTML(true);
    $mail->Subject = 'Form Submission:' . $_POST['subject'];
    $mail->Body = '<h1 align=center>Name:' . $_POST['name'] . '<br>Email:' . $_POST['email'] . '<br>Message:' . $_POST['msg'] . '</h1>';


    if (!$mail->send()) {
        $result = "something went wrong";

    } else {
        $result = "Thanks " . $_POST['name'] . " for contacting us.We'll get back soon!";
    }
}


?>