Comparing Date Fields

          // compare two date fields on a receipt
function validateTravelDates() {
   var receiptDate = NSOA.form.getValue('date');
   var travelDate = NSOA.form.getValue('TravelDate__c');
   
   if ( receiptDate < travelDate ) {
      NSOA.form.error('TravelDate__c', 'The travel date cannot be after the receipt date!');
   }
}