How to Detect When a User Reaches the Bottom of a Web Page?

Identifying Scrolling Position within a Browser Window

Detecting whether a user has reached the bottom of a web page is crucial in enhancing user experience, especially when dynamically adding new content. To establish this functionality, consider the following steps:

JavaScript Implementation

Employ the window.onscroll event listener to monitor the browser's scroll position. Within this listener, determine if the user has reached the bottom of the page using the following formula:

(window.innerHeight + Math.round(window.scrollY)) >= document.body.offsetHeight

where window.innerHeight represents the browser's viewport height, window.scrollY indicates the pixels scrolled vertically, and document.body.offsetHeight provides the total scrollable height of the page.

Demonstration

The provided code snippet provides a demonstration of this technique:

window.onscroll = function(ev) {
    if ((window.innerHeight + Math.round(window.scrollY)) >= document.body.offsetHeight) {
        // User has reached the bottom of the page
    }
};

By incorporating this code into your web application, you can effectively determine if the user has scrolled to the bottom of the page. This allows you to adjust your page's behavior, such as automatically scrolling the user to new content or displaying additional content upon reaching the page's end.

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