如何限制cryptojs模块中特殊字符的生成

// 导入cryptojs模块
const CryptoJS = require('crypto-js');

// 自定义字符集
const customCharset = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';

// 设置生成规则
const random = CryptoJS.lib.WordArray.random;
CryptoJS.lib.WordArray.random = function (nBytes) {
  const words = random.call(this, nBytes);
  const charset = CryptoJS.enc.Utf8.parse(customCharset);
  const mask = charset.words.length - 1;
  for (let i = 0, length = words.words.length; i < length; i++) {
    words.words[i] &= mask;
  }
  return words;
};

// 生成随机字符
const randomString = CryptoJS.lib.WordArray.random(16).toString(CryptoJS.enc.Hex);
console.log(randomString);