JavaScript validate file name extension using check-more-types library
In this JavaScript tutorial we learn how to check whether a file has expected file name extension or not using the check-more-types module.
Create the sample project
Firstly we create an empty project with the following command.
mkdir sample-project
cd sample-project
npm init -yAnd install the check-more-types module using the following command.
npm install check-more-types --saveHow to validate file name extension in JavaScript
In this section we show you how to use the check-more-types library extension() method to check if a given file name string has expected file extension or not.
In the sample-project directory create a new file named check-extension.js as below.
check-extension.js
var check = require('check-more-types');
console.log(check.extension('png', '/path/to/file.png'))
console.log(check.extension('txt', '/path/to/file.png'))
const isJs = check.extension('js');
console.log(isJs('index.js'));
console.log(isJs('index.html'));
Run the check-extension.js file using the following command.
node check-extension.jstrue
false
true
falseMore examples of how to use the check.extension() method
check-extension-examples.js
var check = require('check-more-types');
var fileName = 'index.js';
if(check.extension('js', fileName)) {
console.log(fileName + ' is a JavaScript file.');
} else {
console.log(fileName + ' is not a JavaScript file.');
}
const isJson = check.extension('json');
if(isJson(fileName)) {
console.log(fileName + ' is a JSON file.');
} else {
console.log(fileName + ' is not a JSON file.');
}
Run the check-extension-examples.js file using the following command.
node check-extension-examples.jsindex.js is a JavaScript file.
index.js is not a JSON file.Happy Coding 😊