Set Session in PageMethod (asp.net)

I need to set a couple of Session vars by calling a PageMethod using jQuery.

The client side js looks like this:

function setSession(Amount, Item_nr) {
        //alert(Amount + " " + Item_nr);
        var args = {
            amount: Amount, item_nr: Item_nr
        }
        //alert(JSON.stringify(passingArguments));
       $.ajax({
           type: "POST",
           url: "buycredit.aspx/SetSession",
           data: JSON.stringify(args),
           contentType: "application/json; charset=utf-8",
           dataType: "json",
           success: function () {
               alert('Success.');
           },
           error: function () {
               alert("Fail");
           }
       });

     }

and the server side like this:

[System.Web.Services.WebMethod(EnableSession = true)]
public static void SetSession(int amount, int item_nr)
{
    HttpContext.Current.Session["amount"] = amount;
    HttpContext.Current.Session["item_nr"] = item_nr;
}

only, it seems that the Session vars are not set. When I try to Response.Write out the Session vars, I get nothing. I get no errors, and I can alert out the values passed from the onclick event, to the js function, so they are there.

Can anyone see if I missed something?

Thnx

Solution

Your not getting anything in your session because a null is being passed to the webmethod, use a debugger to step through your javascript and c# to see where its coming from.

The code you posted seems ok as I managed to get it working in a quick test page, so the problem is else where in your code. Here's my test code, hope it helps.

jquery:

$(document).ready(function () {
        $('#lnkCall').click(function () {
            setSession($('#input1').val(), $('#input2').val());
            return false;
        });
    });

    function setSession(Amount, Item_nr) {
        var args = {
            amount: Amount, item_nr: Item_nr
        }

        $.ajax({
            type: "POST",
            url: "buycredit.aspx/SetSession",
            data: JSON.stringify(args),
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function () {
                alert('Success.');
            },
            error: function () {
                alert("Fail");
            }
        });

    }

html:

<div>
    Input1: <input id="input1" type="text" />
    <br />
    Input2 <input id="input2" type="text" />  
    <br />
    <a id="lnkCall" href="#">make call</a>


    <br />
    <asp:Button ID="myButton" runat="server" Text="check session contents" onclick="myButton_Click" />
    <br />
    <asp:Literal ID="litMessage" runat="server" />

</div>

[System.Web.Services.WebMethod(EnableSession = true)]
public static void SetSession(int amount, int item_nr)
{
    HttpContext.Current.Session["amount"] = amount;
    HttpContext.Current.Session["item_nr"] = item_nr;
}


protected void myButton_Click(object sender, EventArgs e)
{
    litMessage.Text = "ammount = " + HttpContext.Current.Session["amount"] + "<br/>item_nr = " + HttpContext.Current.Session["item_nr"];
}