Nodejs/Javascript输出写入所有文件，而不是单个文件

const fs = require('fs');

// 写入文件
fs.writeFile('file1.txt', 'Hello, file1!', (err) => {
  if (err) throw err;
  console.log('file1.txt has been saved!');
});

fs.writeFile('file2.txt', 'Hello, file2!', (err) => {
  if (err) throw err;
  console.log('file2.txt has been saved!');
});

fs.writeFile('file3.txt', 'Hello, file3!', (err) => {
  if (err) throw err;
  console.log('file3.txt has been saved!');
});

// 读取文件
fs.readFile('file1.txt', 'utf8', (err, data) => {
  if (err) throw err;
  console.log('file1.txt content:', data);
});

fs.readFile('file2.txt', 'utf8', (err, data) => {
  if (err) throw err;
  console.log('file2.txt content:', data);
});

fs.readFile('file3.txt', 'utf8', (err, data) => {
  if (err) throw err;
  console.log('file3.txt content:', data);
});