//transform SO to create a new Item fulfillment
var fulfillment = record.transform({
  fromType: record.Type.SALES_ORDER,
  fromId: currentRecord.id,
  toType: record.Type.ITEM_FULFILLMENT,
  isDynamic: true
});

//get line count of newly created fulfillment
var lineCount = fulfillment.getLineCount({
    sublistId: 'item'
});

//for each line set the "itemreceive" field to true
for (var i = 0; i < lineCount; i++) {
  fulfillment.selectLine({
      sublistId: 'item',
      line: i
  });
  fulfillment.setCurrentSublistValue({
      sublistId: 'item',
      fieldId: 'itemreceive',
      value: true
  });

  //set other relevant sublist fields
  fulfillment.setCurrentSublistValue({
      sublistId: 'item',
      fieldId: 'fieldId',
      value: 'value'
  });
  fulfillment.commitLine({
      sublistId: 'item'
  });
}

//set any other relevant itemreceive fields
itemreceive.setValue({
  filedId: 'fieldId',
  value: 'value'
});

//save the newly created itemreceive
var itemreceiveId = itemreceive.save({
  enableSourcing: true, //optional, defaul is false
  ignoreMandatoryFields: true  //optional, defaul is false
});

Hi all, Is there a way for me to use Lineid instead of Line (index) to do transform from sales order to Item fulfillment? Because I'm getting error Null stack

Your not actually doing this are you?

fulfillment.setCurrentSublistValue({
      sublistId: 'item',
      fieldId: 'fieldId',
      value: 'value'
  });

I presume you're supplying relevant fieldId's and value's... As for your Lineid / Line question where are you using either and in what way are you thinking you're using either?

I'm trying to make item fulfillment and use line ID as a key value to populate my inventory detail