Question

I am working in C#.Net. I want to kill the session values when the browser is closed. (i.e) In my application, i want to display online visitors count. If the user clicks logout button means, it works fine. rather than if he close the browser, the session value not cleared.

if the browser close is done, the session value should be killed….

My Global.ascx code…

void Application_Start(object sender, EventArgs e)
{
    // Code that runs on application startup      
    Application["OnlineUsers"] = 0;
}

void Application_End(object sender, EventArgs e)
{
    //  Code that runs on application shutdown
}

void Application_Error(object sender, EventArgs e)
{
    // Code that runs when an unhandled error occurs
}

void Session_Start(object sender, EventArgs e)
{
    Application.Lock();
    Application["OnlineUsers"] = (int)Application["OnlineUsers"] + 1;
    Application.UnLock();
}

void Session_End(object sender, EventArgs e)
{
    Application.Lock();
    Application["OnlineUsers"] = (int)Application["OnlineUsers"] - 1;
    Application.UnLock();
}

My Home.aspx code…

 Visitors online: <%= Application["OnlineUsers"].ToString() %>

If i run my application in IE, the online count will be 1. If i runs in Firefox, the online count should be incresed to 2. If i close the Firefox browser, the count in IE should be changed to 1.

This is my Requirement….

Answer 1

The Http protocol is a connectionless one, so unless you are planning to use websockets, the only two ways to kill the user session should be by a direct request by the user (i.e. pressing a logout link), or a session timeout.

You should not rely on the browser to kill the session. The user can forget to close the browser, or he may have javascript disabled. Instead, provide means to the user to close the session and set your session timeout to a reasonable value adjusted to your users activity.