formatCurrency.js

<script>
   function formatCurrency()
   {
      // Get the values from the text-boxes
      var symbol = document.getElementById('formatCurrencySymbol').value;
      var number = parseFloat(document.getElementById('formatCurrencyNumber').value);
      var decimalPlaces = document.getElementById('formatCurrencyDecimalPlaces').value;
    
      // Do the formatting - Regex here!
      var result = symbol + number.toFixed(decimalPlaces).replace(/(\d)(?=(\d{3})+\.)/g, "$1,");

     // Display the result
     alert(result);
   }
</script>