onmousemove 、onmouseover 、onmouseenter 区别展示

onmousemove 、onmouseover 区别

onmousemove 是鼠标在元素上移动时触发，且在元素上每移动一下就会触发一次。

onmouseover 是鼠标移入元素时触发一次，再次在元素上移动时不会触发，但是鼠标移入元素内的子元素时也会触发（冒泡）

onmouseenter 仅鼠标移入时，触发一次，且不冒泡

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div {
            width: 150px;
            height: 100px;
            border: 1px solid black;
            margin: 10px;
            float: left;
            padding: 30px;
            text-align: center;
            background-color: lightcoral;
        }
        p {
            background-color: white;
        }
    </style>
</head>
<body>
    <h3>该实例演示了 onmousemove, onmouseenter 和 onmouseover 的不同。</h3> 
    <p>onmousemove 是鼠标在元素上移动时触发，且在元素上每移动一下就会触发一次。 </p>
    <p>onmouseover 是鼠标移入元素时触发一次，再次在元素上移动时不会触发，但是鼠标移入元素内的子元素时也会触发（冒泡） </p>
    <p>onmouseenter仅鼠标移入时，触发一次，且不冒泡  </p>
   
    <hr>
    <div onmousemove="myMoveFunction()"> 父元素<p>onmouseenter: <br>  <span id="demo">子元素</span></p> </div> 
    <div onmouseenter="myEnterFunction()"> 父元素<p>onmouseenter: <br> <span id="demo2">子元素</span></p> </div> 
    <div onmouseover="myOverFunction()"> 父元素<p>onmouseover: <br> <span id="demo3">子元素</span></p> </div> 
</body>
<script>
    var x = 0,y = 0,z = 0;
    function myMoveFunction() {
        console.log('====')
        document.getElementById("demo").innerHTML = z+=1;
    }
    
    function myEnterFunction() {
        document.getElementById("demo2").innerHTML = x+=1;
    }
    
    function myOverFunction() {
        document.getElementById("demo3").innerHTML = y+=1;
    }
</script>
</html>
<!DOCTYPE html>