sel_date.aspx :     <script language="javascript">        function GetDate()        {            var reVal=window.showModalDialog("day.aspx", '',                "status:no;center:yes;scroll:no;resizable:no;help:no;dialogWidth:340px;dialogHeight:250px");            if(reVal!="")            {            document.formAct.txt_receive_date.value=reVal;  //返回所選的日期            };        };    </script>------------------------------------------------day.aspx    protected void Calendar1_SelectionChanged(object sender, EventArgs e)    {        string sel_date = Calendar1.SelectedDate.ToShortDateString();        Response.Write("<script>window.returnValue=" + sel_date + ";</script>");        Response.Write("<script>window.close();</script>");    } 問題是返回的時候：總是出現選擇2008-09-01確是1998等錯誤的信息