Хранение сессии ASP.NET, открытой / живой
Вы делаете это тот же самый путь. Вставьте строку как первый оператор в модуле.
2 ответа
I use JQuery to perform a simple AJAX call to a dummy HTTP Handler that does nothing but keeping my Session alive:
function setHeartbeat() {
setTimeout("heartbeat()", 5*60*1000); // every 5 min
}
function heartbeat() {
$.get(
"/SessionHeartbeat.ashx",
null,
function(data) {
//$("#heartbeat").show().fadeOut(1000); // just a little "red flash" in the corner :)
setHeartbeat();
},
"json"
);
}
Session handler can be as simple as:
public class SessionHeartbeatHttpHandler : IHttpHandler, IRequiresSessionState
{
public bool IsReusable { get { return false; } }
public void ProcessRequest(HttpContext context)
{
context.Session["Heartbeat"] = DateTime.Now;
}
}
The key is to add IRequiresSessionState, otherwise Session won't be available (= null). The handler can of course also return a JSON serialized object if some data should be returned to the calling JavaScript.
Made available through web.config:
<httpHandlers>
<add verb="GET,HEAD" path="SessionHeartbeat.ashx" validate="false" type="SessionHeartbeatHttpHandler"/>
</httpHandlers>
added from balexandre on August 14th, 2012
I liked so much of this example, that I want to improve with the HTML/CSS and the beat part
change this
//$("#heartbeat").show().fadeOut(1000); // just a little "red flash" in the corner :)
into
beatHeart(2); // just a little "red flash" in the corner :)
and add
// beat the heart
// 'times' (int): nr of times to beat
function beatHeart(times) {
var interval = setInterval(function () {
$(".heartbeat").fadeIn(500, function () {
$(".heartbeat").fadeOut(500);
});
}, 1000); // beat every second
// after n times, let's clear the interval (adding 100ms of safe gap)
setTimeout(function () { clearInterval(interval); }, (1000 * times) + 100);
}
HTML and CSS
<div class="heartbeat">♥</div>
/* HEARBEAT */
.heartbeat {
position: absolute;
display: none;
margin: 5px;
color: red;
right: 0;
top: 0;
}
here is a live example for only the beating part: http://jsbin.com/ibagob/1/
Do you really need to keep the session (do you have data in it?) or is it enough to fake this by reinstantiating the session when a request comes in? If the first, use the method above. If the second, try something like using the Session_End event handler.
If you have Forms Authentication, then you get something in the Global.asax.cs like
FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(formsCookie.Value);
if (ticket.Expired)
{
Request.Cookies.Remove(FormsAuthentication.FormsCookieName);
FormsAuthentication.SignOut();
...
}
else
{ ...
// renew ticket if old
ticket = FormsAuthentication.RenewTicketIfOld(ticket);
...
}
And you set the ticket lifetime much longer than the session lifetime. If you're not authenticating, or using a different authentication method, there are similar tricks. Microsoft TFS web interface and SharePoint seem to use these - the give away is that if you click a link on a stale page, you get authentication prompts in the popup window, but if you just use a command, it works.