email validation

Validate an email address.

 simple
$email = 'mail@example.com';
$validation = filter_var($email, FILTER_VALIDATE_EMAIL);

if ( $validation ) $output = 'proper email address';
else $output = 'wrong email address';

echo $output;


 advanced
$email="test@geemail.com";
if (isValidEmail($email))
{
       echo "Hooray! Adress is correct.";
}
else
{
       echo "Sorry! No way.";
}

Check-Function
function isValidEmail($email)
{
       Perform a basic syntax-Check
       If this check fails, there's no need to continue
       if(!filter_var($email, FILTER_VALIDATE_EMAIL))
       {
               return false;
       }

       extract host
       list($user, $host) = explode("@", $email);
       check, if host is accessible
       if (!checkdnsrr($host, "MX") && !checkdnsrr($host, "A"))
       {
               return false;
       }

       return true;
}