public void ProcessRequest(HttpContext context)
        {
            String pick_up_point = context.Request.QueryString["pick_up_point"];
            //Debug.WriteLine(pick_up_point);
            CBusPassBO BO = new CBusPassBO();
            var res = BO.SelectABus(pick_up_point);
            JavaScriptSerializer js = new JavaScriptSerializer();

            //String r = js.Serialize(res);
            //Debug.WriteLine(r);
            context.Response.ContentType = "text/plain";
            context.Response.Write(js.Serialize(res));
        }