PHP代码应该是什么，以便我可以接收提交其电子邮件地址的人的电子邮件地址

我已经将contact.html中提供的新闻稿订阅框与newsletter.php链接

但是，当我试图将订阅框中的电子邮件地址发送到邮箱时，我没有收到订阅框中给出的电子邮件地址，而是收到一封空白邮件

contact.html代码

<div class="form-element">
            <form action="newsletter.php" method="post">

                <input name="email" type="email" placeholder="Email" required><span><a  href="newsletter.php"><i type="submit" class="fas fa-chevron-right"></i></a></span>
            </form>
                </div>

newsletter.php代码

<?php
$visitor_email = $_POST['email'];
$email_from = 'info@unboxproduct.in';
$email_subject = "Newsletter Subscribtion";
$email_body = "Subscriber Email: $visitor_email.\n";
$to = "info@unboxproduct.in";
$headers = "From: $email_from \r\n";
$headers .= "Reply-To: $visitor_email \r\n";
mail($to,$email_subject,$email_body,$headers);
header("Location: contact.html");

?>

---

表格代码：-

<div class="form-element">
  <form action="newsletter.php" method="post">
   <input name="email" type="email" placeholder="Email" required>
  <i type="submit" class="fas fa-chevron-right"><input type="submit" name="submit" value="Email Now"></i>
   </form>
</div>

<?php



$visitor_email = $_POST['email'];
$email_from = 'info@unboxproduct.in';
$email_subject = "Newsletter Subscribtion";
$email_body = "Subscriber Email: $visitor_email.\n";
$to = "info@unboxproduct.in";
$headers = "From: $email_from \r\n";
$headers .= "Reply-To: $visitor_email \r\n";
mail($to,$email_subject,$email_body,$headers);
header("Location: contact.html");

?>

邮件代码：-

<div class="form-element">
  <form action="newsletter.php" method="post">
   <input name="email" type="email" placeholder="Email" required>
  <i type="submit" class="fas fa-chevron-right"><input type="submit" name="submit" value="Email Now"></i>
   </form>
</div>

<?php



$visitor_email = $_POST['email'];
$email_from = 'info@unboxproduct.in';
$email_subject = "Newsletter Subscribtion";
$email_body = "Subscriber Email: $visitor_email.\n";
$to = "info@unboxproduct.in";
$headers = "From: $email_from \r\n";
$headers .= "Reply-To: $visitor_email \r\n";
mail($to,$email_subject,$email_body,$headers);
header("Location: contact.html");

?>

您的表单没有提交按钮。使用a href只需将用户重定向到newsletter.php，这与提交表单不同。你需要一个合适的提交按钮。可能需要一个关于html表单的教程请更正我的php代码，然后我想使用fa chevron right作为提交按钮。您可以在按钮中使用它，而不是在链接中使用它