Window: scroll() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The scroll() method of the Window interface scrolls the window to a particular place in the document.
Syntax
scroll(xCoord, yCoord)
scroll(options)
Parameters
xCoord-
The pixel along the horizontal axis of the document that you want displayed in the upper left.
yCoord-
The pixel along the vertical axis of the document that you want displayed in the upper left.
options-
An object containing the following properties:
topOptional-
Specifies the number of pixels along the Y axis to scroll the window or element.
leftOptional-
Specifies the number of pixels along the X axis to scroll the window or element.
behaviorOptional-
Determines whether scrolling is instant or animates smoothly. This option is a string that must take one of the following values:
smooth: The scrolling animates smoothly.instant: The scrolling happens instantly in a single jump.auto: The scroll behavior is determined by the computed value of thescroll-behaviorCSS property on the element.
If omitted,
behaviordefaults toauto.
Return value
A Promise that fulfills with an object containing the following property:
interrupted-
A boolean value indicating whether the scrolling operation was interrupted (
true) or not (false). Such an interruption typically happens when a programmatic scroll is ongoing, and another programmatic scroll is initiated on the window before the first one finishes.
Examples
>Basic usage
// Put the 100th vertical pixel at the top of the window
window.scroll(0, 100);
Using options:
window.scroll({
top: 100,
left: 100,
behavior: "smooth",
});
Responding to the end of the scroll
Our window methods demo (see source code) demonstrates how the promise return value of scroll() can be used to respond to the end of a scrolling operation. This technique is mostly useful in cases where the scrolling occurs smoothly over time (achieved by setting the behavior option to smooth, or by setting the scrolling element's scroll-behavior property to smooth).
HTML
Our HTML includes several paragraphs of content and a <div> element toolbar containing <button> elements that trigger various scrolling operations on the window.
<div>
<button class="scroll">scroll() to 1000</button>
<button class="scrollto">scrollTo() top</button>
<button class="scrollby">scrollBy() 200</button>
</div>
<p>...</p>
<p>...</p>
...
CSS
We give the :root element a scroll-behavior property value of smooth so that any scroll operations are animated smoothly over time rather than instantly.
:root {
scroll-behavior: smooth;
}
We also create two class selectors; when a fade-out or fade-in class is applied to an element, an animation is applied so that it smoothly fades out or in, respectively. We also define @keyframes blocks to define the required opacity changes for those animations.
.fade-out {
animation: fade-out 0.3s linear both;
}
.fade-in {
animation: fade-in 0.3s linear both;
}
@keyframes fade-out {
from {
opacity: 1;
}
to {
opacity: 0;
}
}
@keyframes fade-in {
from {
opacity: 0;
}
to {
opacity: 1;
}
}
The rest of the CSS is not shown, for brevity.
JavaScript
We start by grabbing references to the <button> that runs the scroll() operation and the toolbar <div>:
const scrollBtn = document.querySelector(".scroll");
const toolbar = document.querySelector("div");
When the button is clicked, we immediately apply the fade-out class to the toolbar, causing it to fade out. We then run scroll(0, 1000) on the window to scroll its content down 1000 pixels, awaiting its promise resolution as we do so and storing the result in a constant. When the promise has resolved, we log a message to say that the scroll operation has finished and whether it was interrupted. Finally, we apply the fade-in class to the toolbar, causing it to fade back in again.
scrollBtn.addEventListener("click", async () => {
toolbar.className = "fade-out";
const result = await window.scroll(0, 1000);
console.log(
`Scroll finished;${result.interrupted ? " " : " not "}interrupted`,
);
toolbar.className = "fade-in";
});
The code not relevant to scroll() is not shown, for brevity.
Result
Load our window methods demo (see source code) in a new tab and click the buttons to see the scrolling behavior. Note how the toolbar fades out when a button is pressed, and fades in again once the smooth scrolling is finished.
Try pressing one button and then quickly pressing another button before the first scrolling operation has finished. Open your browser's JavaScript console and note how, in these cases, the scrolling is reported as interrupted.
Specifications
| Specification |
|---|
| CSSOM View Module> # dom-window-scroll> |