// JavaScript Document
function checkform ( form )
{
if (form.email.value == "") {
form.email.focus();
form.email.className = "inputreq";
document.getElementById("label_email").setAttribute("class", "label_inputreq");
alert( "Please enter your email address");
return false ;
}
var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
var address = form.email.value;
if(reg.test(address) == false) {
  alert('Invalid Email Address');
  return false;
}
return true ;
}