How to clear server variables on unload via ajaxRequest

[Josh Turpen]

I've been having some trouble clearing server variables during unload events of pages using RadAjaxManager.

If I click on a link which navigates away from the page, I need to clear a session variable before continuing.  

TestPage.aspx page:
       <telerik:RadAjaxManager runat="server" ID="RadAjaxManager1" OnAjaxRequest="OnAjaxRequest"  />
        ....
        <a href="google.com">google!</a>
        ...
        <telerik:RadScriptBlock runat="server">
            <script type="text/javascript">
                function onunload(sender, args) {
                    var ajaxManager = $find("<%= RadAjaxManager.GetCurrent(Page).ClientID %>");
                    ajaxManager.ajaxRequest("pageUnload");                    
                }
                Sys.Application.add_unload(onunload);
            </script>
        </telerik:RadScriptBlock>

TestPage.aspx.cs code:

        protected void OnAjaxRequest(object sender, AjaxRequestEventArgs e)
        {

            if (e.Argument == "pageUnload")
            {
                Session["someSessionVar"] = null;
            }

      }

Unfortunately this does not work.  After the OnAjaxRequest event, the browser remains on the TestPage.aspx.  It does not continue navigating to the original link clicked (google.com).  

How can I set a server variable when a page is navigated away from? 

Thanks,
Josh

[Genti]

Hello Josh Turpen,

Thank you for contacting us.

I do not know what your scenario is, however I would suggest you handle this situation in the following way:
1) Replace the anchor element with a server control:
<asp:LinkButton Text="linkbutton" runat="server" OnClick="goAway" />
2) Then handle the click in code behind. There you can clear the session and redirect the user to some other page:

protected void goAway(object sender, EventArgs e)
{
    Session["someSessionVar"] = null;
    Response.Redirect("http://www.google.com", false);
}

Hope this helps.

Greetings,
Genti
the Telerik team

[Josh Turpen]

Handling the issue with a server link button doesn't work if the user navigates away from the page via the browser's URL or back button.  This is why I'm trying to handle the issue using the clientside event onunload and sending an ajax request to clear the variable.

Thanks,
Josh

[Genti]

Hi Josh Turpen,

Thank you for the clarification.

In such case, I am following your implementation and providing a sample application that illustrates how the session is cleared.

Hope this helps.

Best wishes,
Genti
the Telerik team