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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style type="text/css">
body {
background: grey;
}
</style>
<script type="text/javascript">
function connected() {
console.log('连接成功，跳转到登录页');
window.location = 'http://localhost:83/login.html';
}
function tryAgain() {//测试60s大概尝试连接90次，可限定200次后不再尝试
console.log('连接失败，尝试再次连接');
document.getElementById('detect').src = 'http://localhost:83/images/logo.png?i=' + Math.random();//因为图片缓存原因，增加随机变量
}
</script>
</head>
<body>
<img id="detect" src="" onload="connected()" onerror="tryAgain()" />
</body>
</html>