js 错误

Question

  在<asp:ScriptManager ID="ScriptManager1" runat="server">             </asp:ScriptManager>    <ContentTemplate>              <asp:UpdatePanel ID="UpdatePanel1" runat="server">            <asp:DropDownList  ID="ddlroom" runat="server"                 onselectedindexchanged="ddlroom_SelectedIndexChanged">           </asp:DropDownList> </ContentTemplate>             </asp:UpdatePanel> 中的 ddlroom_SelectedIndexChanged 事件使用一下代码            System.Web.HttpContext.Current.Response.Write("<script>window.location=window.location</script>");总是出错 为什呀