N/util Module
util.each(iterable, callback)
Method Description: Iterates over each member in an Object or Array. This method calls the callback function on each member of the iterable.
Returns: The original collection as an Object | Array
Supported Script Types: All script types For more information, see SuiteScript 2.0 Script Types.
Governance: None
Module: N/util Module
Since: 2016.1
Search NetSuite - https://system.netsuite.com/app/help/helpcenter.nl?search=util.each(iterable, callback)

// Code Example 1

//Add additional code

//...

// Iterate through the object and set the key-value pairs on the record

util.each(itemList, function(quantity, itemId){

    rec.selectNewLine('item');

    rec.setCurrentSublistValue('item','item',itemId);

    rec.setCurrentSublistValue('item','quantity',quantity);

    rec.commitLine('item');

  });

//...

//Add additional code



//SOURCE: https://system.netsuite.com/app/help/helpcenter.nl?fid=section_4541697371.html