How to convert hex string into a bytes array, and a bytes array in the hex string?

Convert a hex string to a byte array and vice versa

note: implementation from crypto-js

// Convert a hex string to a byte array
function hexToBytes(hex) {
    for (var bytes = [], c = 0; c < hex.length; c += 2)
        bytes.push(parseInt(hex.substr(c, 2), 16));
    return bytes;
}

// Convert a byte array to a hex string
function bytesToHex(bytes) {
    for (var hex = [], i = 0; i < bytes.length; i++) {
        var current = bytes[i] < 0 ? bytes[i] + 256 : bytes[i];
        hex.push((current >>> 4).toString(16));
        hex.push((current & 0xF).toString(16));
    }
    return hex.join("");
}