UTF-32的nodejs缓冲区toString函数

Question

我正在处理一个二进制文件，我试图使用 NodeJs 解析并存储为变量。我的文件当前在缓冲区中。这部分文件根据需求文档是UTF-32。

41 00 00 00  55 00 00 00  54 00 00 00  4F 00 00 00 
31 00 00 00  45 00 00 00  30 00 00 00  33 00 00 00 
38 00 00 00  31 00 00 00  31 00 00 00  36 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00

var string_UserName = data.toString('utf-8', 96, 179);
console.log('User Name: ' + string_UserName);
//User Name: A   U   T   O   1   E   0   3   8   1   1   6

var string_UserName = data.toString('utf-16le', 96, 179);
console.log('User Name: ' + string_UserName);
//User Name: A U T O 1 E 0 3 8 1 1 6

var string_UserName = data.toString('utf-32le', 96, 179);
console.log('User Name: ' + string_UserName);
//buffer.js:387
      throw new TypeError('Unknown encoding: ' + encoding);
      ^
TypeError: Unknown encoding: utf-32le
    at Buffer.slowToString (buffer.js:387:17)
    at Buffer.toString (buffer.js:399:31)

根据Node Documentation for Buffer，没有内置东西可以转换为字符串utf-32。

是否有一个 NPM 模块可以扩展 BUFFER 以允许这种转换，或者我是否需要编写一个 buffer.prototype.toString() 函数来扩展 toString()，这将允许这种转换发生？如果是这样，是否有人已经拥有了他们使用的一个？

---

这是文件前 256/FF 字节的十六进制转储。

AF 03 00 00  D0 00 00 00  16 81 03 1E  0A 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
41 00 00 00  55 00 00 00  54 00 00 00  4F 00 00 00 
31 00 00 00  45 00 00 00  30 00 00 00  33 00 00 00 
38 00 00 00  31 00 00 00  31 00 00 00  36 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  32 30 31 36  30 31 32 32  31 32 33 35 
34 32 30 30  30 30 30 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00 
00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00

使用@vlad 的回答后

Iconv = require('iconv').Iconv;
var convertUTF32 = new Iconv('UTF-32', 'UTF-8');
var string_UserName = convertUTF32.convert(data.slice(96, 179));
console.log('User Name: ' + string_UserName);

我收到来自 ICONV 的错误：

C:\nodeCode\node_modules\iconv\lib\iconv.js:145
          throw errnoException('EINVAL', 'Incomplete character sequence.');
          ^

Error: Incomplete character sequence.
    at errnoException (C:\nodeCode\node_modules\iconv\lib\iconv.js:169:13)
    at Object.convert (C:\nodeCode\node_modules\iconv\lib\iconv.js:145:17)
    at Iconv.convert (C:\nodeCode\node_modules\iconv\lib\iconv.js:59:12)
    at C:\nodeCode\metaProc.js:49:37
    at FSReqWrap.readFileAfterClose [as oncomplete] (fs.js:404:3)
    at fs.js:312:11
    at nextTickCallbackWith0Args (node.js:456:9)
    at process._tickCallback (node.js:385:13)

有人建议这是因为 data.slice(96, 179) 不是 4 的倍数，但我无法理解因为 96 如果第一个字节和 179 是 4 字节组的最后一个字节（176、177、178、179 ）。 180 将是下一个字节的开始而不是结束。

任何帮助将不胜感激。

---

终于弄清楚我做错了什么。虽然@Vlad 基本上是对的。我那里没有//TRANSLIT//IGNORE，也不得不移动结束索引1，因为buffer.slice 似乎是Half-Closed Interval [96, 180) 而不是inclusive [96, 179]，就像我想的那样。

我真正需要的是：

Iconv = require('iconv').Iconv;
var iconv32 = new Iconv('UTF-32LE', 'UTF-8//TRANSLIT//IGNORE');
var string4_UserName = iconv32.convert(data.slice(96,180)).toString('utf-8');
console.log('User Name: ' + string4_UserName);

Answer 1

是的，有一个iconv npm module 经常用于缓冲区解码。

根据它的README，你可以试试：

var Iconv  = require('iconv').Iconv;
var iconv = new Iconv('UTF-32LE', 'UTF-8');
var string_UserName = iconv.convert(data.slice(96, 179)).toString('utf8');
console.log('User Name: ' + string_UserName);

让我知道它是否适合你。