Determining Scroll Direction with jQuery
When working with scroll events in jQuery, distinguishing between upward and downward movement can be crucial for implementing scrolling behavior. This code snippet demonstrates how to detect the direction of a scroll event:
<br>$(window).scroll(function(event){<br> var st = $(this).scrollTop();<br> if (st > lastScrollTop){</p> <pre class="brush:php;toolbar:false"> // downscroll code
} else {
// upscroll code
}
lastScrollTop = st;
});
Here, we maintain a variable (lastScrollTop) to record the previous scroll position. By comparing the current scroll position (st) with lastScrollTop, we can determine the direction of the scroll. If st is greater than lastScrollTop, it indicates a downward scroll; otherwise, it's an upward scroll.
This technique is straightforward and effectively captures the scrolling direction, allowing you to implement appropriate actions for both upscroll and downscroll events.
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