在标头中使用变量时不发送电子邮件

Question

I am creating a contact form and for some reason when I use variables int he header, the email isn't getting sent. This one works:

$first_name = (isset($_POST['firstname']) ? $_POST['firstname'] : null);
$last_name = (isset($_POST['lastname']) ? $_POST['lastname'] : null);
$email = (isset($_POST['email']) ? $_POST['email'] : null);
$message = (isset($_POST['message']) ? $_POST['message'] : null);
$mail_to = "MyEmail";
$subject = "Subject";
$headers =  'MIME-Version: 1.0' . "
";
$headers .= 'From: '.$first_name.' '.$last_name.' <[e-mail]>' . "
";
$headers .= 'Content-type: text/html; charset=iso-8859-1' . "
";
mail($mail_to, $subject, $message, $headers)

and this one doesn't

$first_name = (isset($_POST['firstname']) ? $_POST['firstname'] : null);
$last_name = (isset($_POST['lastname']) ? $_POST['lastname'] : null);
$email = (isset($_POST['email']) ? $_POST['email'] : null);
$message = (isset($_POST['message']) ? $_POST['message'] : null);
$mail_to = "MyEmail";
$subject = "Subject";
$headers =  'MIME-Version: 1.0' . "
";
$headers .= 'From: '.$first_name.' '.$last_name.' <'.$email.'>'."
";
$headers .= 'Content-type: text/html; charset=iso-8859-1' . "
";
mail($mail_to, $subject, $message, $headers)

I am talking about these lines:

$headers .= 'From: '.$first_name.' '.$last_name.' <[e-mail]>'."
";
$headers .= 'From: '.$first_name.' '.$last_name.' <'.$email.'>'."
";

This works until I add the email variable into the headers, could someone explain me what I am doing wrong?

Answer 1

Try to put the variable inside Your name <>