How to get the File Extension of a File using Node

Because Node is a back-end language, it runs on the server and can perform file system operations.
A common operation is needing to know what the extension of a file is.
In this post, we'll learn how to get the file extension of a file on the file system using Node.
How to get the file extension of a file
Getting the file extension of a file is easy thanks to the built-in path
module.
This module has the extname
method that can be used to get the file extension of a file.
Simply pass it the path of a valid file and it will return the file extension.
import * as path from "path";
const ext = path.extname("/path/to/file.txt");
console.log(ext);
.txt
In case you have a file name with numerous dots, the extname
method will return the file extension of the last dot.
import * as path from "path";
const ext = path.extname("/path/to/file.txt.zip");
console.log(ext);
.zip
Keep in mind that if the file has no extension, it will return a blank string:
import * as path from "path";
const ext = path.extname("/path/to/file");
console.log(ext);
Conclusion
In this post, we learned how to get the file extension of a file using Node.
Simply import the path
module and use the extname
method with a valid file path.
Thanks for reading and happy coding!
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