react native encoding conversion -

i'm trying convert fetch response iso-8859-1 utf-8 in react native. found answer : encoding conversion of fetch response in react native i'm having troubles...

i didn't manage use iconv, tryed :

npm install --save iconv-lite // success 

then do

var iconv = require('iconv-lite') // error 500 react native 

i didn't manage use buffer, unknown react native and

require('buffer').buffer // error 500 react native 

so here questions :

what best way make encoding conversion in react native ?
in case encoding conversion of fetch response good: how use iconv ? how use buffer ?