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POJavaScript: Stop SetInterval if no response
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copied!<p>I'm using an alternate code to <code>navigator.OnLine</code> to check for network connection. It works, however, I'm having some issues with it.</p> <p>If I'm connected/disconnected to the network inside the intranet (corporate network) , then I have no issues whatsoever. However, if I'm home and I'm connected to my home network, but not connected to the corporate intranet using a VPN connection, then the window will freeze for 10 second intervals. I think it's because there's internet connection, but the server is unreachable because I'm disconnected from the intranet.</p> <p>Here's the code:</p> <pre><code>function serverReachable() { // IE vs. standard XHR creation var x = new ( window.ActiveXObject || XMLHttpRequest )( "Microsoft.XMLHTTP" ), s; x.open( // requesting the headers is faster, and just enough "HEAD", // append a random string to the current hostname, // to make sure we're not hitting the cache "http://16.24.163.33" + window.location.hostname + "/?rand=" + Math.random(), // make a synchronous request false ); try { x.send(); s = x.status; // Make sure the server is reachable return ( s >= 200 && s < 300 || s === 304 ); // catch network & other problems } catch (e) { return false; } } </code></pre> <p>What I would like to do with your help, is to cancel a request that takes more than one second. So if I'm trying to reach 16.24.163.33 from home, and no response was received after 1 (!) second, then cancel the request, and retry this whole code again in two minutes.</p> <pre><code>setInterval(function () { if (serverReachable()) { if (timeout === null) { var changeIt = document.getElementById('change') changeIt.style.visibility = 'hidden'; timeout = setInterval("refreshIframe()",25000); } } else { clearTimeout(timeout); timeout = null; var changeIt = document.getElementById('change') changeIt.style.visibility = 'visible'; } }, 900); </code></pre>

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