Category: Advanced JavaScript

Recent Post

What is a Blob object in JavaScript?

A Blob object is used for accessing, encoding and transferring files and file-like objects.

How to save and retrieve images from localStorage

You can use the FileReader API to create a data URL and pass this through localStorage.

How to create and decode a query string in JavaScript

A query string is used to store string data as part of a URL.

How to read and display a PDF using JavaScript

The native FileReader API can be used to read a PDF and create a URL to its contents.

A guide to using localStorage and sessionStorage

localStorage and sessionStorage objects allow you to store data from to user's browser.

map() vs forEach()

The map() and forEach() methods both iterate through arrays, but are not interchangeable.

Understanding JavaScript closures with simple examples

A JavaScript closure is a function that has its own protected, 'private' variables.

A very simple introduction to JavaScript modules

Learn how to better organise code using reusable JavaScript modules.

Filter an existing array to make a new one using filter()

Create a new array including only certain elements from an existing array using filter()

Make array calculations with the reduce() method

Reduce the values of an array to a single number with reduce()