// JavaScript Document
function validateFormOnSubmit(theForm) {
var reason = "";

  reason += validateEmpty(theForm.FirstName);
  reason += validateEmpty(theForm.LastName);
  reason += validateEmpty(theForm.Email);
  reason += validateEmpty(theForm.Subject);
  reason += validateEmpty(theForm.Message);
      
  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    return false;
  }

  return true;
}
function validateEmpty(fld) {
    var error = "";
 
    if (fld.value.length == 0) {
        fld.style.background = 'Red'; 
        error = "The required field has not been completed.\n"
    } else {
        fld.style.background = 'White';
    }
    return error;  
}