N/util Module
util.isArray(obj)
Method Description: Returns true if the obj parameter is a JavaScript Array object and false otherwise.
Returns: boolean
Supported Script Types: All script types For more information, see SuiteScript 2.0 Script Types.
Governance: None
Module: N/util Module
Global object: util Object
Since: 2016.1
Search NetSuite - https://system.netsuite.com/app/help/helpcenter.nl?search=util.isArray(obj)

// Code Example 1

//Add additional code

//...

var records = ["Sales Order", "Invoice", "Item Fulfillment"];

util.isArray(records); // returns true



var record = "Sales Order";

util.isArray(record); // returns false

//...

//Add additional code



//SOURCE: https://system.netsuite.com/app/help/helpcenter.nl?fid=section_4434638201.html