移入 移出mouseenter mouseleave
在父盒子上触发，在孩子盒子上不触发
移入 移出mouseover mouseout全触发
html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
#box{
width: 200px;
height: 200px;
background: yellow;
}
#child{
width: 100px;
height: 100px;
background: red;
}
</style>
</head>
<body>
<div id="box">鼠标移入移出
<div id="child"></div>
</div>
<script>
// 移入 移出mouseover mouseout
// 都触发
box.onmouseover = function(){
console.log("鼠标移入")
}
box.onmouseout = function(){
console.log("鼠标移出")
// 移入 移出mouseenter mouseleave
// 在父盒子上触发，在孩子盒子上不触发
box.onmouseenter = function(){
console.log("鼠标移入")
}
box.onmouseleave = function(){
console.log("鼠标移出")
}
</script>
</body>
</html>