confirm--显示一个带有指定消息和 OK 及取消按钮的对话框
用户点击ok返回true，点击取消返回false
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body><script type="text/javascript">function confirmDemo(){var boo = window.confirm("你带刺吗？");if(boo){alert("111");}else{alert("222");}}</script><button οnclick="confirmDemo();">confirm</button>
</body>
</html>