SummaryEdit
Returns the number of pixels that the document has already been scrolled vertically.
SyntaxEdit
var y = window.scrollY;
y
is the number of pixels that the document is currently scrolled from the top.
ExampleEdit
// make sure and go down to the second page
if (window.scrollY) {
window.scroll(0, 0); // reset the scroll position to the top left of the document.
}
window.scrollByPages(1);
NotesEdit
Use this property to check that the document hasn't already been scrolled some if you are using relative scroll functions such as window.scrollBy
, window.scrollByLines
, or window.scrollByPages
.
The pageYOffset
property is an alias for the scrollY
property:
window.pageYOffset == window.scrollY; // always true
For cross-browser compatibility, use window.pageYOffset
instead of window.scrollY
. Additionally, older versions of Internet Explorer (< 9) do not support either property and must be worked around by checking other non-standard properties. A fully compatible example:
var supportPageOffset = window.pageXOffset !== undefined;
var isCSS1Compat = ((document.compatMode || "") === "CSS1Compat");
var x = supportPageOffset ? window.pageXOffset : isCSS1Compat ? document.documentElement.scrollLeft : document.body.scrollLeft;
var y = supportPageOffset ? window.pageYOffset : isCSS1Compat ? document.documentElement.scrollTop : document.body.scrollTop;
SpecificationEdit
Specification | Status | Comment |
---|---|---|
CSS Object Model (CSSOM) View Module The definition of 'window.scrollY' in that specification. |
Working Draft |
Browser compatibilityEdit
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | Edge | (Yes) | (Yes) |