fs js code example

Example 1: readfilesync

const fs = require('fs')

try {
  const data = fs.readFileSync('/Users/joe/test.txt', 'utf8')
  console.log(data)
} catch (err) {
  console.error(err)
}

Example 2: node open file

const fs = require("fs");

// __dirname means relative to script. Use "./data.txt" if you want it relative to execution path.
fs.readFile(__dirname + "/data.txt", (error, data) => {
    if(error) {
        throw error;
    }
    console.log(data.toString());
});

Example 3: nodejs readfile

const fs = require('fs');

fs.readFile('/Users/joe/test.txt', 'utf8' , (err, data) => {
  if (err) {
    console.error(err);
    return
  }
  console.log(data);
});

Example 4: fs.writefile

const fs = require('fs');

fs.writeFile("/tmp/test", "Hey there!", function(err) {
    if(err) {
        return console.log(err);
    }
    console.log("The file was saved!");
}); 

// Or
fs.writeFileSync('/tmp/test-sync', 'Hey there!');

Example 5: node js write file

// fs_write.js

const fs = require('fs');

// specify the path to the file, and create a buffer with characters we want to write
let path = 'ghetto_gospel.txt';
let buffer = new Buffer('Those who wish to follow me\nI welcome with my hands\nAnd the red sun sinks at last');

// open the file in writing mode, adding a callback function where we do the actual writing
fs.open(path, 'w', function(err, fd) {
    if (err) {
        throw 'could not open file: ' + err;
    }

    // write the contents of the buffer, from position 0 to the end, to the file descriptor returned in opening our file
    fs.write(fd, buffer, 0, buffer.length, null, function(err) {
        if (err) throw 'error writing file: ' + err;
        fs.close(fd, function() {
            console.log('wrote the file successfully');
        });
    });
});

Example 6: fs writefile node

const fs = require('fs')

const content = 'Some content!'

fs.writeFile('/Users/joe/test.txt', content, err => {
  if (err) {
    console.error(err)
    return
  }
  //file written successfully
})