Page Comparison

function() {
  var email = document.getElementById("sMailAddress").value;
  var reg = new RegExp("^[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$");
  
  if (reg.test(email) == true) {
    return email;
  } else {
    return "";
  }
}