Byte array to hexadecimal and back again in JavaScript [closed]

Question

I can generate a byte array with

var myByteArray = window.crypto.getRandomValues(new Uint8Array(16))

and I get

181,143,16,173,231,56,63,149,181,185,224,124,84,230,123,36

I can then turn this into a string with

cryptoHelpers.convertByteArrayToString(myByteArray);

and i get

µ­ç8?µ¹à|Tæ{$

But what I really want is a 128 bit hexadecimal like...

6a3e52297b2e593f4d506f7164

And I want to be able to go back from hexadecimal to a byte array.

Is there a copy and paste function or library to make this magic happen?

Answer 1

Here's something you can copy-paste in.

byteArray = new Uint8Array([181,143,16,173,231,56,63,149,181,185,224,124,84,230,123,36]);
function toHexString(byteArray) {
  return Array.prototype.map.call(byteArray, function(byte) {
    return ('0' + (byte & 0xFF).toString(16)).slice(-2);
  }).join('');
}
function toByteArray(hexString) {
  var result = [];
  for (var i = 0; i < hexString.length; i += 2) {
    result.push(parseInt(hexString.substr(i, 2), 16));
  }
  return result;
}
hexString = toHexString(byteArray);
byteArray = toByteArray(hexString);

From here/here.