connect_check.html - Android社区 - https://www.androidos.net.cn/

<!DOCTYPE html>
<html>
<head>
<title>test ws connection</title>
<script type="text/javascript">
var protocol = location.protocol.replace('http', 'ws');
var url = protocol + '//' + location.host + '/echo-with-no-extension';
// Do connection test.
var ws = new WebSocket(url);

ws.onopen = function()
{
  // Set document title to 'PASS'. The test observer catches this title changes
  // to know the result.
  document.title = 'PASS';
}

ws.onclose = function()
{
  // Set document title to 'FAIL'.
  document.title = 'FAIL';
}

</script>
</head>
</html>