Thank you, Sir.
I check from console and see some attribute was generate by Easyui eg. textboxname, comboname
So I was change attribute value to new_id too. It does work.
// for textboox
$('#old_id').attr('id', 'new_id').attr('name', 'new_id').attr('textboxname', 'new_id');
// and change hidden input to
$('.textbox-value[name="old_id"]').attr("name", new_id);