c# - Change ajax returned status code

Question

I have the following web metod:

[WebMethod]

    public static string SayHello()
    {
        if (HttpContext.Current.Session["UserData"] != null)
        {
                  //do something
        }

        else
        {
            response.StatusCode = 401;
            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.StatusCode = 401;
            throw new HttpException(401, "timeout");
        }
    }

and this is the call:

$.ajax({
    url: 'Default.aspx/SayHello',
    type: 'POST',
    contentType: 'application/json; charset=utf-8',
    async: false,
    dataType: "json",
    data: '{ }',
    success: function(Result) {


        //do something
    },
    error: function(xhr, textStatus, errorThrown) {
             xhr.StatusCode = 500
    }
});

I always get 500 (Internal Server Error) status code in $.ajax error var xhr.StatusCode Can I change it inside the WebMethod?

I want to change it to 401 (Unauthorized) and inside $.ajaxError redirect to the login page..