protected void Page_Load(object sender, EventArgs e)
 {
     if (Session["UserId"] != null)
     {
         LBtnToLogin.Visible = false;
         LoginStatus.Visible = true;
         lblUserName.Text    = Session["UserName"].ToString();
         cartNum.InnerHtml   = CartSiv.GetTotalCartNum(int.Parse(Session["UserId"].ToString())).ToString();
         HeadImage.ImageUrl  = "HeadImage.aspx?id=" + Session["UserId"];
     }
     else
     {
         LBtnToLogin.Visible = true;
         LoginStatus.Visible = false;
     }
 }