无法逐行读取文件

Question

我正在尝试逐行读取文件。

在this answer之后，这是我的代码：

const fs = require("fs");
const readline = require("readline");

const stream = fs.createReadStream("file.txt");
stream.on("error", err => console.log("Error: " + err));
const reader = readline.createInterface({input: stream});

reader.on("line", function (line) {
  console.log(line);
});

但是，什么也没打印。

这是reader对象的内容：

Interface {
  _sawReturnAt: 0,
  isCompletionEnabled: true,
  _sawKeyPress: false,
  _previousKey: null,
  domain: null,
  _events:
   { close: { [Function: bound onceWrapper] listener: [Function: onSelfCloseWithoutTerminal] } },
  _eventsCount: 1,
  _maxListeners: undefined,
  output: undefined,
  input:
   ReadStream {
     _readableState:
      ReadableState {
        objectMode: false,
        highWaterMark: 65536,
        buffer: [Object],
        length: 0,
        pipes: null,
        pipesCount: 0,
        flowing: true,
        ended: false,
        endEmitted: false,
        reading: false,
        sync: true,
        needReadable: false,
        emittedReadable: false,
        readableListening: false,
        resumeScheduled: true,
        destroyed: false,
        defaultEncoding: 'utf8',
        awaitDrain: 0,
        readingMore: false,
        decoder: null,
        encoding: null },
     readable: true,
     domain: null,
     _events: { end: [Array], error: [Function], data: [Function: ondata] },
     _eventsCount: 3,
     _maxListeners: undefined,
     path: 'file.txt',
     fd: null,
     flags: 'r',
     mode: 438,
     start: undefined,
     end: Infinity,
     autoClose: true,
     pos: undefined,
     bytesRead: 0 },
  historySize: 30,
  removeHistoryDuplicates: false,
  crlfDelay: 100,
  _prompt: '> ',
  terminal: false,
  _decoder:
   StringDecoder {
     encoding: 'utf8',
     fillLast: [Function: utf8FillLast],
     lastNeed: 0,
     lastTotal: 0,
     lastChar: <Buffer 2d 00 00 00> } }

我在这里到底想念什么？

谢谢！