Node.js

💾 File system

📖 Reading files

Promises

import { readFile } from 'fs/promises';

try {
  const data = await readFile('file.txt', 'utf8');
  console.log(data);
} catch (err) {
  console.error(err);
}

Callback

import { readFile } from 'fs';

readFile('file.txt', 'utf8', (err, data) => {
  if (err) {
    console.error(err);
    return;
  }
  console.log(data);
});

Synchronous

import { readFileSync } from 'fs';

try {
  const data = readFileSync('file.txt', 'utf8');
  console.log(data);
} catch (err) {
  console.error(err);
}

📝 Writing files

Promises

import { writeFile } from 'fs/promises';

try {
  writeFile('file.txt', 'hello world');
} catch (err) {
  console.error(err);
}

Callback

import { writeFile } from 'fs';

writeFile('file.txt', 'hello world', (err) => {
  if (err) {
    console.error(err);
  }
});

Synchronous

import { writeFileSync } from 'fs';

try {
  writeFileSync('file.txt', 'hello world');
} catch (err) {
  console.error(err);
}