N/record Module
record.Sublist
Object Description: Encapsulates a sublist on a standard or custom record. For a complete list of this object’s methods and properties, see Sublist Object Members.
Supported Script Types: Client and server-side scripts For more information, see SuiteScript 2.0 Script Types.
Module: N/record Module
Since: 2015.2
Search NetSuite - https://system.netsuite.com/app/help/helpcenter.nl?search=record.Sublist

// Code Example 1

// Add additional code.

//...

var objRecord = record.load({

   type: record.Type.SALES_ORDER,

   id: 275

});



var objSublist = objRecord.getSublist({

   sublistId: 'item'

});

if(objSublist.type === 'inlineeditor'){

   //Perform an action

}

//...

// Add additional code.



//SOURCE: https://system.netsuite.com/app/help/helpcenter.nl?fid=section_4600574625.html