nodejs实现txt文件上传下载

以下是使用Node.js实现txt文件上传和下载的代码示例：

上传文件：

const http = require('http');
const fs = require('fs');

const server = http.createServer((req, res) => {
  if (req.method === 'POST') {
    const fileStream = fs.createWriteStream('file.txt');
    req.pipe(fileStream);
    req.on('end', () => {
      res.writeHead(200, { 'Content-Type': 'text/plain' });
      res.end('File uploaded successfully!');
    });
  } else {
    res.writeHead(200, { 'Content-Type': 'text/html' });
    res.end(`
      <form action="/" method="post" enctype="multipart/form-data">
        <input type="file" name="file" /><br /><br />
        <input type="submit" value="Upload" />
      </form>
    `);
  }
});

server.listen(8080, () => {
  console.log('Server is running on port 8080');
});

下载文件：

const http = require('http');
const fs = require('fs');

const server = http.createServer((req, res) => {
  if (req.method === 'GET' && req.url === '/download') {
    const fileStream = fs.createReadStream('file.txt');
    res.writeHead(200, {
      'Content-Type': 'application/octet-stream',
      'Content-Disposition': 'attachment; filename=file.txt',
    });
    fileStream.pipe(res);
  } else {
    res.writeHead(200, { 'Content-Type': 'text/html' });
    res.end(`
      <a href="/download">Download file</a>
    `);
  }
});

server.listen(8080, () => {
  console.log('Server is running on port 8080');
});