if(preg_match("/^([a-zA-Z0-9])+([\.[a-zA-Z0-9_-]+])*@([a-zA-Z0-9_-])+(\.[a-zA-Z0-9_-]+)*\.([a-zA-Z]{2,6})$/", $val)) {
[/^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$/i]