mouseenter事件只會觸發一次,觸發對象是注冊對象或者注冊對象的子元素
mouseover事件可以觸發多次,觸發對象是注冊對象或者注冊對象的子元素
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<p>不論鼠標指針穿過被選元素或其子元素,都會觸發 mouseover 事件。</p>
<p>只有在鼠標指針穿過被選元素時,才會觸發 mouseenter 事件。</p>
<div class="over" style="background-color:lightgray;padding:20px;width:40%;float:left">
<h2 style="background-color:white;">被觸發的 Mouseover 事件:<span></span></h2>
</div>
<div class="enter" style="background-color:lightgray;padding:20px;width:40%;float:right">
<h2 style="background-color:white;">被觸發的 Mouseenter 事件:<span></span></h2>
</div>
<script>
var x = 0,y = 0;
var div1 = document.getElementsByClassName("over")[0];
div1.addEventListener("mouseover",function(){
var span = this.getElementsByTagName("span")[0]
span.innerText = (x +=1);
span.style.cssText = "border:2px red solid;";
},false);
var div2 = document.getElementsByClassName("enter")[0];
div2.addEventListener("mouseenter",function(){
var span = this.getElementsByTagName("span")[0]
span.innerText = (y +=1);
span.style.cssText = "border:2px red solid;";
},false);
</script>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<p>不論鼠標指針穿過被選元素或其子元素,都會觸發 mouseover 事件。</p>
<p>只有在鼠標指針穿過被選元素時,才會觸發 mouseenter 事件。</p>
<div class="over" style="background-color:lightgray;padding:20px;width:40%;float:left">
<h2 style="background-color:white;">被觸發的 Mouseover 事件:<span></span></h2>
</div>
<div class="enter" style="background-color:lightgray;padding:20px;width:40%;float:right">
<h2 style="background-color:white;">被觸發的 Mouseenter 事件:<span></span></h2>
</div>
<script>
var x = 0,y = 0;
var div1 = document.getElementsByClassName("over")[0];
div1.addEventListener("mouseover",function(){
var span = this.getElementsByTagName("span")[0]
span.innerText = (x +=1);
span.style.cssText = "border:2px red solid;";
},false);
var div2 = document.getElementsByClassName("enter")[0];
div2.addEventListener("mouseenter",function(){
var span = this.getElementsByTagName("span")[0]
span.innerText = (y +=1);
span.style.cssText = "border:2px red solid;";
},false);
</script>
</body>
</html>
