javascript中级--事件冒泡即取消冒泡
一、事件冒泡
<!DOCTYPE html>
<html lang="en" onclick="alert( 'html')">
<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>事件冒泡</title>
</head>
<body onclick="alert('body')">
<div style="width:400px;height:400px;background:red" onclick="alert('red')">
<div style="width:200px;height:200px;background:blue" onclick="alert('blue')">
<div style="width:100px;height:100px;background:#ccc;" onclick="alert('gray')"></div>
</div>
</div>
</body>
</html>
二、取消冒泡
<!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>
#menu {
width: 100px;
height: 300px;
background: #ccc;
margin-top: 10px;
display: none;
}
</style>
<script>
window.onload = function() {
var oBtn = document.getElementById('btn1');
var oMenu = document.getElementById('menu');
oBtn.onclick = function(ev) {
var oEvent = ev || event;
oMenu.style.display = "block";
// alert('a');
oEvent.cancelBubble = "true"; //阻止冒泡
}
document.onclick = function() {
oMenu.style.display = "none";
}
}
</script>
</head>
<body>
<input id="btn1" type="button" name="" value="弹出">
<div id="menu"></div>
</body>
</html>
