protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                HttpCookie myCookie = Request.Cookies["Login"];
                if (myCookie != null && myCookie.Values["UserName"] != null && myCookie.Values["Password"] != null)
                {
                    //取出Cookie中的值，显示到文本框中，
                    txtUserName.Text = Request.Cookies["Login"]["UserName"].ToString();
                    txtPassword.Text = Request.Cookies["Login"]["Password"].ToString();
                }
            }
        }

        //点击登陆按钮，保存Cookie中的值，跳转到另一个页面，另一个页面有个HyperLink，点击又跳转到登陆页面
        protected void btnLogin_Click(object sender, EventArgs e)
        {
            if (txtUserName.Text == "admin" && txtPassword.Text == "123")
            {
                Response.Cookies["Login"]["UserName"] = txtUserName.Text.Trim();
                Response.Cookies["Login"]["Password"] = txtPassword.Text.Trim();
                Response.Cookies["Login"].Expires = DateTime.Now.AddDays(Convert.ToDouble(5));
                Response.Redirect("Test.aspx");
            }
        }