Cfgui.js addPortItem Function - Need more information

Hi,

I'm trying to understand how the property set "instancePropSet" gets its values in the addPortItem function of cfgui.js. It gets the quote/order line item details like 'Product Id', 'Port Item Id' etc. Is it possible to get the value of 'Quote Item Id' OOTB field as well?

Any pointers will be really appreciated.

function addPortItem (tableId, instancePropSet)

{

   var hasGeneric = "";

   var intId      = "";

   var innerHTML  = "";

   var inputValue = "";

   var table      = null;

   var tr         = null;

   var td         = null;

   var prodId     = "";

   var quantity   = 0;

   var NoQtyCtrl  = "";

   var strDynDisable = "N";

   var readOnlyVal = "";

   var strDisplayName ="";

   var fieldListPropSet  = new JSSCfgPropertySet ();

   var strFieldList  = instancePropSet.GetProperty ("FieldList");

   fieldListPropSet.DecodeFromString (strFieldList);