如何设置发件人的电子邮件仅从特定域发送？

Question

For example, i only want the sender's email is from "[e-mail]", if other email like "[e-mail]" is not allow, only @abc.com is allowed. How should i do that?

let say $_POST['Sender']="[e-mail]";

$to = "[e-mail]";
$subject = "Test mail";
$message = "Hello! This is a simple email message.";
$from = $_POST['Sender'];
$headers = "From:" . $from;

mail($to,$subject,$message,$headers);
echo "Mail Sent.";

Answer 1

you should be able to just wrap it within an if statement:

$to = "[e-mail]";
$subject = "Test mail";
$message = "Hello! This is a simple email message.";
$from = $_POST['Sender'];
$headers = "From:" . $from;

if ($from === "[e-mail]") {
    mail($to,$subject,$message,$headers);
    echo "Mail Sent.";
}