Ajax call to Page Methods

Folks,

Recently I got to work on a .NET based Security Token Service and faced an issue where I needed to call a web method from with in the page without creating a new session, normally whenever we use ajax call we get a new session which would redirect us back to the login page of the Application as it doesn't know whether the call was from the authenticated user or what.

Anyway, so I hope you all understand the issue. The main purpose of the function was to get the data from the session for a particular key, I know first thing that comes to your mind would be that I must have used

<%=Session['key']%>

Which is what we use all the time but no this time the scenario was different. I had to get the value because I had an Iframe in the page which was changing the value of that particular key. So what I did was, I googled a bit and got to know about PageMethods. So here it is how I used it


Paste this in your form tag:



<asp:ScriptManager ID="ScriptManagerMain" runat="server" EnablePageMethods="true"
        ScriptMode="Release" LoadScriptsBeforeUI="true">
    </asp:ScriptManager>

And use the javascript:

  function onSuccess(data) {
            window.location = data;
        }
        function onFailure(error) {
            window.location = 'where-ever-I-wanted-it-to-go';
        }
        function GetCurrentSessionValue() {
            // call server side method
            PageMethods.GetSessionValue(onSuccess, onFailure);
        }

This is my Code Behind where I wrote this method.

 [WebMethod]
        public static string GetSessionValue()
        {
           return HttpContext.Current.Session["RedirectUrl"].ToString();
        }


I hope it helps. For any query just post a comment and I will get back to you.