Handling the back button in a web browser is something many web developers need to do. It’s important because you might want to do something special when a user tries to go back to the previous page. In JavaScript, there are ways to know when the back button is clicked or when the URL changes. We’ll look at a simple way to detect browser back button event in Javascript.
Issue Faced
The main issue faced by developers is how to trigger an event when the user clicks the back button or when there are changes in the URL. Traditional event listeners may not capture these specific actions, leading to challenges in implementing desired functionalities.
Methods to detect browser back button event in Javascript
Here let’s take a look at three methods in which you can detect browser back button events in JavaScript:
Method 1- Using `beforeunload` Event
javascript
window.addEventListener('beforeunload', () => {
console.log('User clicked back button');
});
The `beforeunload` event is triggered just before the document is unloaded, which includes navigating away from the page using the back button. However, note that this event is also triggered when the user closes the tab or refreshes the page.
Method 2- Using `popstate` Event
javascript
window.addEventListener('popstate', () => {
console.log('User clicked back button');
});
The `popstate` event is specifically designed to handle navigation within the browsing context’s history stack, including back and forward button clicks. This event provides more control over detecting back button actions.
Method 3- Using `hashchange` Event
javascript
window.addEventListener('hashchange', event => {
console.log('Fragment identifier or URL changed');
});
The `hashchange` event is triggered when there is a change in the fragment identifier (the part of the URL after the ‘#’) or when the URL itself changes. While not directly related to the back button, this event can be useful for tracking URL changes that may occur during navigation.
Conclusion
By following these methods like beforeunload, popstate and hashchange developers can easily detect browser back button events. And also address the associated challenges in triggering actions based on user navigation. Web development agencies can utilise these techniques to create more interactive and responsive web applications.