From: 011netservice@gmail.com
Date: 2022-05-22
Subject: ByteArrayToUTF8.txt

歡迎來信交流

---------- 2022-05-22, #### ByteArrayToUTF8
ref:
https://stackoverflow.com/questions/17191945/conversion-between-utf-8-arraybuffer-and-string

function stringToUint(string) {
    var string = btoa(unescape(encodeURIComponent(string))),
        charList = string.split(''),
        uintArray = [];
    for (var i = 0; i < charList.length; i++) {
        uintArray.push(charList[i].charCodeAt(0));
    }
    return new Uint8Array(uintArray);
}

function uintToString(uintArray) {
    var encodedString = String.fromCharCode.apply(null, uintArray),
        decodedString = decodeURIComponent(escape(atob(encodedString)));
    return decodedString;
}

I have done, with some help from the internet, these little functions, they should solve your problems! 
Here is the working JSFiddle. 如下(20220523-1).

EDIT:
Since the source of the Uint8Array is external and you can't use atob you just need to remove it(working fiddle):
如下(20220523-2):
function uintToString(uintArray) {
    var encodedString = String.fromCharCode.apply(null, uintArray),
        decodedString = decodeURIComponent(escape(encodedString));
    return decodedString;
}


有空時看看這篇:
Warning: escape and unescape is removed from web standards. See this.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/escape

(20220523-1): http://jsfiddle.net/DQJyX/
function stringToUint(string) {
  var string = btoa(unescape(encodeURIComponent(string))),
    charList = string.split(''),
    uintArray = [];
  for (var i = 0; i < charList.length; i++) {
    uintArray.push(charList[i].charCodeAt(0));
  }
  return new Uint8Array(uintArray);
}

function uintToString(uintArray) {
  var encodedString = String.fromCharCode.apply(null, uintArray),
    decodedString = decodeURIComponent(escape(atob(encodedString)));
  return decodedString;
}
var str = "€",
  enc = stringToUint(str),
  dec = uintToString(enc);
console.log(enc);
console.log(dec);


(20220523-2): http://jsfiddle.net/Z9pQE/2/
var array = new Uint8Array(3);
array[0] = 0xe2;
array[1] = 0x82;
array[2] = 0xac;

function uintToString(uintArray) {
    var encodedString = String.fromCharCode.apply(null, uintArray),
        decodedString = decodeURIComponent(escape(encodedString));
    return decodedString;
}

console.log(uintToString(array)); // €

若應用在 huge arrays, 則可能會碰到錯誤.
解決方法為改用 .slice(), 應用在 塊狀資料中.
You saved my day! 
Just one addition, that if you use it with huge arrays, you can easily get: [Error] RangeError: Maximum call stack size exceeded. 
To fix that I use .slice() and apply it in chunks