1// writefile.js
2
3const fs = require('fs');
4
5let lyrics = 'But still I\'m having memories of high speeds when the cops crashed\n' + 
6             'As I laugh, pushin the gas while my Glocks blast\n' + 
7             'We was young and we was dumb but we had heart';
8
9// write to a new file named 2pac.txt
10fs.writeFile('2pac.txt', lyrics, (err) => {
11    // throws an error, you could also catch it here
12    if (err) throw err;
13
14    // success case, the file was saved
15    console.log('Lyric saved!');
16});
17

1const fs = require('fs');
2
3fs.writeFile("/tmp/test", "Hey there!", function(err) {
4    if(err) {
5        return console.log(err);
6    }
7    console.log("The file was saved!");
8}); 
9
10// Or
11fs.writeFileSync('/tmp/test-sync', 'Hey there!');

1const fs = require('fs');
2
3fs.readFile('/Users/joe/test.txt', 'utf8' , (err, data) => {
4  if (err) {
5    console.error(err);
6    return
7  }
8  console.log(data);
9});

1const fs = require('fs');
2
3fs.readFile('file.txt', 'utf-8', (err, data) => {
4    if(err) {
5        throw err;
6    }
7    console.log(data);
8});
9

1// write_stream.js
2
3const fs = require('fs');
4
5let writeStream = fs.createWriteStream('secret.txt');
6
7// write some data with a base64 encoding
8writeStream.write('aef35ghhjdk74hja83ksnfjk888sfsf', 'base64');
9
10// the finish event is emitted when all data has been flushed from the stream
11writeStream.on('finish', () => {
12    console.log('wrote all data to file');
13});
14
15// close the stream
16writeStream.end();
17

1fs.readFile('filename', function read(err, data) {
2    if (err) {
3        throw err;
4    }
5    var content = data;
6  
7    console.log(content);  
8   
9});