Working with Files: How to get the file extension in Node.js

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I had the need to find the extension of a file.

I had the name of the file, in my case an image, and wanted to get the extension (.jpg, .png..).

To do this, you can use the path built-in module and its extname() method:

const path = require('path')

path.extname('picture.png') //.png
path.extname('picture.of.a.dog.png') //.png
path.extname('picture.of.a.dog.jpg') //.jpg
path.extname('picture.of.a.dog.jpeg') //.jpeg

Lessons in this unit:

0:	Introduction
1:	How to check if a file exists in Node.js
2:	How to create an empty file in Node.js
3:	How to get the names of all the files in a folder in Node
4:	How to get the last updated date of a file using Node.js
5:	How to remove a file with Node.js
6:	How to write a JSON object to file in Node.js
7:	How to empty a folder in Node.js
8:	Working with file descriptors in Node
9:	Node File Paths
10:	Node file stats
11:	Working with folders in Node
12:	How to use the Node.js fs module with async/await
13:	How to get the current folder in Node
14:	How to get the file extension in Node.js from the MIME type
15:	▶︎ How to get the file extension in Node.js
16:	How to list files in a folder in Node
17:	How to mass rename files in Node.js
18:	Node.js get all files in a folder recursively
19:	Incrementing multiple folders numbers at once using Node.js
20:	Save some text to a file in Node.js