div居中显示 div弹出框 alert（渐渐消失）

先看效果

前台代码

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="div弹出居中.aspx.cs" Inherits="div弹出居中" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>无标题页</title>

    <script src="scripts/jquery-1.3.2.min.js" type="text/javascript"></script>

    <script language="javascript" type="text/javascript">
function divcenter(i)
{
var divId=document.getElementById('div1sss');
document.getElementById('div1sss').innerHTML=i;
document.getElementById("div1sss").style.display="block";
$("#div1sss").fadeOut(13000,function(){});

}

function attachWindowEventHandler(event,func)
  {
    if(navigator.appName == 'Netscape')
    {
          window.addEventListener(event,func,false);
   }
   else
   {
         window.attachEvent('onload',func);
   }
}
    </script>

    <style type="text/css">
        #div1sss
        {
            position: absolute;
            top: 50%;
            left: 50%;
            margin-top: -25px;
            margin-left: -150px;
            color: blue;
             300px;
            height: 50px;
            font-weight: bold;
            border: solid 1px gray;
            line-height: 50px;
            font-size: 20px;
            text-align: center;</style>
</head>
<body>
    <form id="form1" runat="server">
    <table width="100%">
        <tr>
            <td>
                <asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" />
                <span onclick="divcenter()">test</span>
            </td>
        </tr>

    </table>
    <div id="div1sss" style="display: none; position: absolute; background-color: yellow;">
    </div>
      </form>
  </body>
</html>

后台代码

protected void Button1_Click(object sender, EventArgs e)
    {
        Utility.MessageBox.AlertScript("attachWindowEventHandler('',function(){divcenter('成功');})");
    }