function checkmail() {
    var e = document.forms["emailForm"].elements["email"]
    var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
    var address = e.value;
    //alert(address)
    if (reg.test(address) == false) {
        alert('Invalid Email Address');
        return false;
    }
    else {
        return true;
    }
}