var msg;
  
  function checkMandatoryField(elementName,labelText){
    document.getElementById(elementName).style.backgroundColor = '#FFFFFF';
    if(document.getElementById(elementName).value==''){
      msg += '     ' + labelText + '\n';
      document.getElementById(elementName).style.backgroundColor = '#FFDFDF';
    }
  }
  
  function validateForm(){
    msg = '';
    document.getElementById('cmdSubmit').value = 'Validating ...';
    
    checkMandatoryField('FirstName','First name');
    checkMandatoryField('LastName','Last name');
    checkMandatoryField('CompanyName','Company name');
    checkMandatoryField('JobTitle','Job title');
    checkMandatoryField('EmailAddress','Business email address');
    checkMandatoryField('Telephone','Work telephone');
    checkMandatoryField('DateTime','Date and time');
    checkMandatoryField('ValidationCode','Validation code');
      
    if(document.getElementById('ValidationCode').value=='') document.getElementById('ValidationCode').focus();
    if(document.getElementById('DateTime').value=='') document.getElementById('DateTime').focus();
    if(document.getElementById('Telephone').value=='') document.getElementById('Telephone').focus();
    if(document.getElementById('EmailAddress').value=='') document.getElementById('EmailAddress').focus();
    if(document.getElementById('JobTitle').value=='') document.getElementById('JobTitle').focus();
    if(document.getElementById('CompanyName').value=='') document.getElementById('CompanyName').focus();
    if(document.getElementById('LastName').value=='') document.getElementById('LastName').focus();
    if(document.getElementById('FirstName').value=='') document.getElementById('FirstName').focus();

    if(msg.length>0){
      alert('Please provide the following information:\n\n' + msg);
      document.getElementById('cmdSubmit').value = 'Request Demo';
      return false;
    }
    else{
      document.getElementById('cmdSubmit').value = 'Requesting ...';
      return true;
    }
  }