is there a way to validate an email in this form without rewriting it completely? It'd be great if I could just add something to this. I'm new to PHP and this form is taken from mmtuts video. If you know how to help, I'd be glad if you did.
<?php
if (isset($_POST['submit'])) {
$name = $_POST['name'];
$number = $_POST['number'];
$subject = $_POST['subject'];
$mailFrom = $_POST['mail'];
$message = $_POST['message'];
$mailTo = "misavoz@seznam.cz";
$headers = "From: ".$mailFrom;
$txt = "Pan/í ".$name." vám poslal/a zprávu. Telefonní číslo: ".$number."\n\n".$message;
mail($mailTo, $subject, $txt, $headers);
header("Location: index.php?mailsend");
}