<html>
<head>
<title>事件流</title>
<meta charset="utf-8"></head>
<body>
<div id="box">
<a href="http://www.baidu.com" id="go" onclick="stopgoto()">go</a>
</div>
<script type="text/javascript">
function stopgoto(event){
alert("hello");
event.stopPropagation();
event.stopDefault();
}
</script>
</body>
</html>
你这个事件流，并没有定义a的父元素div的事件，没所谓的阻止不阻止，a的stopPropagation是阻止冒泡到div，不是阻止自身事件动作
<html>
<head>
<title>事件流</title>
<meta charset="utf-8">
</head>
<body>
<div id="box" style="height: 100px;width: 50px;border-radius: 50px 50px;background-color: green;">
<a href="http://www.baidu.com" target="_blank" onclick="stopgoto(event)">go</a>
</div>
<script type="text/javascript">
window.onload = function() {
var div = document.getElementById("box");
box.onclick = function() {
alert("imooc");
}
}
function stopgoto(event) {
alert("hello");
event.stopPropagation();
}
</script>
</body>
</html>