Optimizing web pages to work across browsers can be a daunting task. This is especially true of using the latest JavaScript features such as ES6 modules. Although these features are very useful, they are not supported by all older browsers, which can lead to problems with the display of pages or unavailability of functionality for users with older browsers.
What to do in such cases? You can use the Polyfill.io service, which provides the ability to automatically connect polyphiles (that is, code that complements the missing functions in older browsers), depending on the browser used by the user. This means that you can use modern JavaScript features without having to worry about supporting them in older browsers.
One example of using Polyfill.io can be seen in the following example:In this example, we use a tag to connect Polyfill.io to our page. In the URL parameters we pass a list of functions that we want to support, such as , , , ,
<script src="//polyfill.io/v3/polyfill.min.js?flags=gated&features=default,es5,es6,es7,matchMedia,IntersectionObserver,ResizeObserver,NodeList.prototype.forEach,HTMLTemplateElement,Element.prototype.closest,requestAnimationFrame,CustomEvent,URLSearchParams,queueMicrotask" nomodule></script>
etc. In particular, es6es5es7 es6 modules are listed as defaultone of the functions that we want to support.
script We also pass a parameter nomodulethat means that this script tag does not have to be executed if the browser supports ES6 modules
What is Polyfill.io?
Polyfill.io is a free service that allows you to connect polyphiles depending on the capabilities of the browser that opens the web page. Polyphiles are pieces of code that add new features to older browsers that don't support these built-in features.
To use Polyfill.io, you need to include the script in your HTML code. Here's an example:
<script src="//polyfill.io/v3/polyfill.min.js?flags=gated&features=default,es5,es6,es7,matchMedia,IntersectionObserver,ResizeObserver,NodeList.prototype.forEach,HTMLTemplateElement,Element.prototype.closest,requestAnimationFrame,CustomEvent,URLSearchParams,queueMicrotask" nomodule></script>
So now we know that Polyfill.io can be a very useful service to ensure that older browsers are compatible with the latest web standards, such as ES6 modules. Now let's take a closer look at how it works and how you can use this service in your project.
First of all, what is a polyphile? In computer science, polyphiles are code snippets that provide missing functionality in a particular environment, including browsers, operating systems, and other platforms. For example, if you want to use a new JavaScript method that is not supported by all browsers, you can write a polyphile that provides this functionality, regardless of whether the browser supports this method or not.
Once you have added a script tag from Polyfill.io to your page, it automatically analyzes the user's browser and returns the necessary polyphiles if needed. If the browser supports all the functions specified in the script tag, then the request to Polyfill.io will be ignored.
If you are using a framework or library, such as React, Vue, or Angular, you may need to add certain polyphiles to support the features of these frameworks in older browsers. For example, React needs a polyphile to support the method Object.assign() in Internet Explorer 11.
So, using the Polyfill.io service, you can provide support for older browsers for your web application without additionally downloading extra code for browsers that already support ES6 modules.
The following code shows you how to use Polyfill.io to support ES6 modules and React features:
<script src="//polyfill.io/v3/polyfill.min.js?flags=gated&features=default,es5,es6,es7,matchMedia,IntersectionObserver,ResizeObserver,NodeList.prototype.forEach,HTMLTemplateElement,Element.prototype.closest,requestAnimationFrame,CustomEvent,URLSearchParams,queueMicrotask,Object.assign" nomodule></script>
<script src="https://unpkg.com/[email protected]/umd/react.production.min.js"></script>
<script src="https://unpkg.com/[email protected]/umd/react-dom.production.min.js"></script>
Given that the service Polyfill.io automatically analyzes the user's browser and returns only the necessary polyphiles, you do not need to add separate code for each browser you want to support. This makes it quite convenient and easy to use.
So, in this article we have examined in detail the Polyfill.io service, which allows you to automatically add polyphiles to maintain functionality in older browsers. We learned how Polyfill.io works and how you can customize its use for your website. Also, we looked at an example of using Polyfill.io to add polyphiles for ES6 modules, which allows you to support their work in older browsers.
The application of the Polyfill.io service is very important to ensure that your website is as compatible as possible with different browsers. Thanks to this, you will be able to ensure that your website works on all devices and browsers, and users will not face trouble interacting with it. Remember that users use different browsers and devices, so maximum compatibility of your website is a very important element of its success.
