node.js修改文件数据流？

const fs = require('fs');

const readStream = fs.createReadStream('input.txt');
const writeStream = fs.createWriteStream('output.txt');

readStream.on('data', (chunk) => {
  // 修改数据流
  const modifiedChunk = modifyData(chunk);
  writeStream.write(modifiedChunk);
});

readStream.on('end', () => {
  writeStream.end();
});

const fs = require('fs');

const readStream = fs.createReadStream('input.txt');
const writeStream = fs.createWriteStream('output.txt');

readStream.on('data', (chunk) => {
  // 修改数据流
  const modifiedChunk = modifyData(chunk);
  writeStream.write(modifiedChunk);
});

readStream.on('end', () => {
  writeStream.end();
});

function modifyData(data) {
  // 自定义的数据修改逻辑
  // ...
  return modifiedData;
}