files/en-us/web/api/element/mouseover_event/index.md
{{APIRef("UI Events")}}
The mouseover event is fired at an {{domxref("Element")}} when a pointing device (such as a mouse or trackpad) is used to move the cursor onto the element or one of its child elements.
If the target element has child elements, mouseout and mouseover events fire as the mouse moves over the boundaries of these elements too, not just the target element itself. Usually, mouseenter and mouseleave events' behavior is more sensible, because they are not affected by moving into child elements.
Use the event name in methods like {{domxref("EventTarget.addEventListener", "addEventListener()")}}, or set an event handler property.
addEventListener("mouseover", (event) => { })
onmouseover = (event) => { }
A {{domxref("MouseEvent")}}. Inherits from {{domxref("UIEvent")}} and {{domxref("Event")}}.
{{InheritanceDiagram("MouseEvent")}}
This interface also inherits properties of its parents, {{domxref("UIEvent")}} and {{domxref("Event")}}.
true if the <kbd>alt</kbd> key was down when the mouse event was fired.true if the <kbd>control</kbd> key was down when the mouse event was fired.true if the <kbd>meta</kbd> key was down when the mouse event was fired.true if the <kbd>shift</kbd> key was down when the mouse event was fired.MOZ_SOURCE_* constants).
This lets you, for example, determine whether a mouse event was generated by an actual mouse or by a touch event (which might affect the degree of accuracy with which you interpret the coordinates associated with the event).The following example illustrates the difference between mouseover and {{domxref("Element/mouseenter_event", "mouseenter")}} events.
<ul id="test">
<li>item 1</li>
<li>item 2</li>
<li>item 3</li>
</ul>
const test = document.getElementById("test");
// This handler will be executed only once when the cursor
// moves over the unordered list
test.addEventListener("mouseenter", (event) => {
// highlight the mouseenter target
event.target.style.color = "purple";
// reset the color after a short delay
setTimeout(() => {
event.target.style.color = "";
}, 500);
});
// This handler will be executed every time the cursor
// is moved over a different list item
test.addEventListener("mouseover", (event) => {
// highlight the mouseover target
event.target.style.color = "orange";
// reset the color after a short delay
setTimeout(() => {
event.target.style.color = "";
}, 500);
});
{{EmbedLiveSample('Examples')}}
{{Specifications}}
{{Compat}}