asp.net Timer的使用方法

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Threading;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Label4.Text = "初始化时间：" + DateTime.Now.ToString();
Timer1.Interval = 1000;
}
protected void Timer1_Tick(object sender, EventArgs e)
{
Label3.Text = "刷新时间：" + DateTime.Now.ToString();
}
}