Validate email in PHP

Here is the simple php function by this you can validate email which entered by any user.

public function checkEmail($mailID) {
$pat = "/^[a-zA-Z0-9._-]+@[a-zA-Z0-9-.]+\.[a-zA-Z. ]{2,6}$/";
if(preg_match($pat,$mailID)) {
return true;
} else {
return false;
}
}