The screenX read-only property of the MouseEvent property provides the horizontal coordinate (offset) of the mouse pointer in global (screen) coordinates.
Syntax
var pixelNumber = instanceOfMouseEvent.screenX
Return value
A double floating point value. Early versions of the spec defined this as an integer referring to the number of pixels. See the Browser compatibility section for details.
Example
<html>
<head>
<title>screenX\screenY example</title>
<script type="text/javascript">
function showCoords(evt){
alert(
"screenX value: " + evt.screenX + "\n"
+ "screenY value: " + evt.screenY + "\n"
);
}
</script>
</head>
<body onmousedown="showCoords(event)">
<p>To display the mouse coordinates click anywhere on the page.</p>
</body>
</html>
When you trap events on the window, document, or other roomy elements, you can get the coordinates of that event (e.g., a click) and route it properly, as the following example demonstrates:
function checkClickMap(e) {
if (e.screenX < 50) doRedButton();
if (50 <= e.screenX && e.screenX < 100) doYellowButton();
if (e.screenX >= 100) doRedButton();
}
Specifications
| Specification | Status | Comment |
|---|---|---|
| CSS Object Model (CSSOM) View Module The definition of 'screenX' in that specification. |
Working Draft | Redefines MouseEvent from long to double. |
| Document Object Model (DOM) Level 3 Events Specification The definition of 'MouseEvent.screenX' in that specification. |
Obsolete | No change from Document Object Model (DOM) Level 2 Events Specification. |
| Document Object Model (DOM) Level 2 Events Specification The definition of 'MouseEvent.sceenX' in that specification. |
Obsolete | Initial definition |
Browser compatibility
We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!
| Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | (Yes) | (Yes) | (Yes) | 6 | (Yes) | (Yes) |
Redefined from long to double |
56 | ? | ? | ? | ? | ? |
| Feature | Android Webview | Chrome for Android | Edge | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|---|
| Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Redefined from long to double |
56 | 56 | ? | ? | ? | ? | ? |