See if it can help: https://developer.adobe.com/experience-manager/reference-materials/6-5/forms/javascript-api/GuideBridge.html

Output Service - Typically this service is used to merge XML data with an xdp template or pdf to generate a flattened pdf.   Using the instance manager through javascript you can do easy manipulation of data in a dynamic table.     https://experienceleague.adobe.com/docs/experience-manager-learn/for...

Use the below in the Row3 init event and remove all the script from the Discount field in Row3.   var Disc = xfa.resolveNodes("xfa.record.FormPurchaseOrder.PriceAndTax.PriceComponent[*]").length; var discountMatched = false;for (var i=0; i<=Disc; i++) {var TypeWord = xfa.resolveNode("xfa.record.Form...

As per the email conversation, you can achieve the desired result from below logic. Add the below logic in the init event of Discount field as your all data comes from xml.   if(Row3.Discount.rawValue== 0) then hide > this.Table2.Row3.presence="hidden";

make your else block like below:   else{this.Table2.Row3.presence="hidden";}

You need to break the loop once the desired value is matched, so put "break;" keyword in your if block.   if(TypeWord == "Overall Discount (%)"){this.rawValue = xfa.resolveNode("xfa.record.FormPurchaseOrder.PriceAndTax.PriceComponent["+ i +"].CalculatedAmount").value; break;}

Share your form if you can, need to check the script in the form. vkatoch07@gmail.com on google drive. Thanks

Read the below article too: https://www.eggs.de/en/products/forms/developer-view.html

You need to put it in the enter event of next field, on which it needs to check the dropdown field value, whether it null or not.  

Add a script like the below as per your forms field in the "enter" event.     form1.nextField::enter - (JavaScript, client) if(DropDownList1.rawValue==null || DropDownList1.rawValue==""){DropDownList1.presence = "hidden";}