UpdatePanel 刷新有关问题_ASP.NET

UpdatePanel 刷新问题

C# code

protected void Timer1_Tick(object sender, EventArgs e)    {        DataSet ds = AccessDAL.Books.Books_Tanchu(0, 0);        if (ds.Tables[0].Rows.Count > 0)        {            Literal1.Text = "<div style=\"height:300px;\">";        }        else        {            Literal1.Text = "<div style=\"height:300px;display:none;\">";        }    }

C# code

protected void Page_Load(object sender, EventArgs e)    {        if (!Page.IsPostBack)        {            Timer1_Tick(Timer1, new EventArgs());        }    }

HTML code

        <asp:ScriptManager ID="ScriptManager1" runat="server">        </asp:ScriptManager>        <asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">            <ContentTemplate>        <asp:Timer ID="Timer1" runat="server" Interval="5000" ontick="Timer1_Tick"></asp:Timer>                        <asp:Literal ID="Literal1" runat="server"></asp:Literal>                <div id="msg_win" style="top:503px;overflow: hidden;">                <div class="icos"><a id="msg_min" title="最小化" href="javascript:void 0">_</a><a id="msg_close" title="关闭" href="javascript:void 0">×</a></div>                    <div id="msg_title">通知：</div>                    <div id="msg_content">您好，当前您有信息未读。<a href="Books/books_list.aspx?page=31" target="mainFrame">点击进入</a></div>                </div></div>            </ContentTemplate>                        <Triggers>                            <asp:AsyncPostBackTrigger    ControlID="Timer1" />                        </Triggers>        </asp:UpdatePanel>

为什么一直刷新
但是我做了一个后台更新新闻前台自动更新的就不刷新也是这套代码
大虾们帮看看

------解决方案--------------------------------------------------------
幫你UP下吧

每次回調都可調試的，看有沒有回調不就清楚了，又或是回調處出現異常導致沒刷新，不過你上面是正常的，呵呵
------解决方案--------------------------------------------------------
[code=HTML][/code]<%@ Page Language="C#" AutoEventWireup="true" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Timer Example Page</title>
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
OriginalTime.Text = DateTime.Now.ToLongTimeString();
}

protected void Timer1_Tick(object sender, EventArgs e)
{
StockPrice.Text = GetStockPrice();
TimeOfPrice.Text = DateTime.Now.ToLongTimeString();
}

private string GetStockPrice()
{
double randomStockPrice = 50 + new Random().NextDouble();
return randomStockPrice.ToString("C");
}
</script>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server" />