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Summary
Returns the number of pixels that the document has already been scrolled vertically.
Syntax
var y = window.scrollY;
y
is the number of pixels that the document is currently scrolled from the top.
Example
// 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);
Notes
Use this property to check that the document hasn't already been scrolled when 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;
Specification
Specification | Status | Comment |
---|---|---|
CSS Object Model (CSSOM) View Module The definition of 'window.scrollY' in that specification. |
Working Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Microsoft Edge | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | No support | (Yes) | (Yes) | (Yes) |
Feature | Android | Android Webview | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|---|
Basic support | ? | (Yes) | ? | ? | ? | ? | ? | (Yes) |