If you are building a web app using “Forms” as a mode of authentication, there’s really not much to it when it comes to extending a session automatically.
What I am suggesting is that your web session will extend on its own so long as you have defined slidingExpiration attribute in your web.config file like so:
<authentication mode="Forms">
<forms name=".ASPXAUTH" loginUrl="~/Login.aspx" timeout="20" slidingExpiration="true"></forms>
</authentication>
Now, if you are using the authentication mode as “Windows“, there’s no support for the slidingExpiration attribute. For that, you can implement a solution in jQuery by simply creating a dummy HTML file and calling it anything you like. In the example below, I’ve named it AjaxDemo.html. See code below.
One thing to note here is that I am concatenating Date and Time when making an asynchronous call to AjaxDemo.html. This is done to ensure that a unique value is returned from the server. This step is crucial in extending the session timeout beyond its default threshold of 20 minutes.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://code.jquery.com/jquery-1.10.2.js"></script>
<title>Session Timeout</title>
<script type="text/javascript">
var sessionDelay = 5000; // 5 seconds
$(function () {
$("#btnExtendSession").click( function () {
keepAlive();
});
});
function keepAlive() {
var d = new Date();
$.get('AjaxDemo.html?=' + d.getTime(), function () {
timer = setTimeout(keepAlive, sessionDelay);
clearTimeout(timer);
});
}
</script>
</head>
<body>
<button id="btnExtendSession">Extend Session</button>
</body>
</html>
When you click on the button “Extend Session” and open dev tools, inside the Network tab, you would notice a unique value appended to AjaxDemo.html’s query string. See below:
Hope you found the post useful.
