code: function getStringFromCharCode(dataView, start, length) {
    var str = '';
    var i;
    for (i = start, length += start; i < length; i++) {
      str += String.fromCharCode(dataView.getUint8(i));
    }
    return str;
  }
docs: 步骤二，Unicode码转字符串 ArrayBuffer对象 Unicode码转字符串