When an event is triggerd, the screenX mouse event returns the horizontal coordinate of the mouse pointer.
Example
You can try to run the following code to learn how to implement screenX Mouse event in JavaScript.
<!DOCTYPE html>
<html>
<body>
<p onclick = "coordsFunc(event)">Click here to get the x (horizontal) and y (vertical) coordinates of the mouse pointer.</p>
<script>
function coordsFunc(event) {
var x_coord = event.screenX;
var y_coord = event.screenY;
var xycoords = "X coords= " + x_coord + ", Y coords= " + y_coord;
document.write(xycoords);
}
</script>
</body>
</html>