App下载
实例代码( Tip: 登录后体验更佳 )
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>W3Cschool线(w3cschool.cn)</title>
</head>
<body>
<p>使 HTML DOM body "onbeforeunload" </p>
<p> F5 onbeforeunload </p>
<a href="http://www.w3cschool.cn">W3Cschool线</a>
<script>
window.onbeforeunload = function(event) {
event.returnValue = "西...";
};
</script>
</body>
</html>
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运行结果