node-string-arraybuffer.js

function arraybuffer2str(ab) {
    return String.fromCharCode.apply(null, new Uint16Array(buf));
}

function str2arraybuffer(str) {
    let buf = new ArrayBuffer(str.length * 2);
    let bufView = new Uint16Array(buf);
    for (let i = 0; i < str.length; i++) {
        bufView[i] = str.charCodeAt(i);
    }

    return buf;
}