request获取到的不为当前传入的id
后台代码
public static string userID = System.Web.HttpContext.Current.Request.QueryString["UserID"].ToString();
    //public static string userID = "B222EF78-D0E6-4EF5-991B-F96800E56030";
    [System.Web.Services.WebMethod]
    public static int addEvent(ImproperCalendarEvent improperEvent)
    {
        CalendarEvent cevent = new CalendarEvent()
        {
            userid = userID,
            title = improperEvent.title,
            description = improperEvent.description,
            start =System.DateTime.ParseExact(improperEvent.start, "dd-MM-yyyy hh:mm:ss tt", CultureInfo.InvariantCulture),
            end = System.DateTime.ParseExact(improperEvent.end, "dd-MM-yyyy hh:mm:ss tt", CultureInfo.InvariantCulture),
        };

        if (CheckAlphaNumeric(cevent.title) && CheckAlphaNumeric(cevent.description))
        {
            int key = EventDAO.addevent(cevent);

            List<int> idList = (List<int>)System.Web.HttpContext.Current.Session["idList"];

            if (idList != null)
            {
                idList.Add(key);
            }

            return key;

        }

        return -1;

    }

    private static bool CheckAlphaNumeric(string str)
    {

        if (string.IsNullOrEmpty(str))
            return false;
        else
            return true;


    }

js
$(document).ready(function () {
    $('#updatedialog').dialog({
        autoOpen: false,
        width: 570,
        buttons: {
            "更新": function () {
                var eventToUpdate = {
                    id: currentU