Write the file handling operations in Node JS

In Node.js, the "fs" module is used for file handling operations. Here are the steps to perform some basic file handling operations:

1. Reading a File:

var fs = require('fs');

fs.readFile('test.txt', 'utf8', function(err, data){
    if (err) throw err;
    console.log(data);
});

In this code, we are using the readFile function of the fs module to read the file 'test.txt'. The 'utf8' parameter is used to define the encoding of the file.

2. Writing to a File:

var fs = require('fs');

fs.writeFile('test.txt', 'Hello World!', function(err){
    if (err) throw err;
    console.log('File written!');
});

In this code, we are using the writeFile function of the fs module to write 'Hello World!' to the file 'test.txt'. If the file does not exist, it will be created.

3. Appending to a File:

var fs = require('fs');

fs.appendFile('test.txt', 'Hello again!', function(err){
    if (err) throw err;
    console.log('Data appended!');
});

In this code, we are using the appendFile function of the fs module to append 'Hello again!' to the file 'test.txt'.

4. Deleting a File:

var fs = require('fs');

fs.unlink('test.txt', function(err){
    if (err) throw err;
    console.log('File deleted!');
});

In this code, we are using the unlink function of the fs module to delete the file 'test.txt'.