node filesystem code example

Example 1: 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 2: 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 3: 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 4: read file in nodejs using fs

let myFile = "./myText.txt";
const fs = require("fs");
		
app.all('/test', async (req, res) => {
	try {
		const readData = fs.readFileSync(myFile, 'utf8');
		if (readData) {
			res.send(readData)
		}
	} catch (error) {
		res.send("something is wrong", error)
	}
})

Example 5: 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
})

Example 6: javascript fs read

fs.readFile('/etc/passwd', (err, data) => {
  if (err) throw err;
  console.log(data);
});