How to disable sublist field in a single line in Suitescript 2.0.

Hi team,

I need to disable a field on some of the lines in a sublist using Suitescript 2.0

I tried using lineinit and setting isDisabled = true for a line –

var cancelReason = currentRecord.getSublistField({

sublistId: 'recmachcustrecord_brl_buy_request',

fieldId: "custrecord_brl_cancel_reason",

line: selectedLine

});

1. cancelReason.isDisabled = true;

This disabled the entire column in the whole sublist.

Is there a way I can achieve this, is it possible in a before load if not in the client script ?

Thanks in advance