protected void Page_Load(object sender, EventArgs e)
 {
     if (!checkCookie())
         Response.Redirect("Login.aspx");
     String sellerUsername = Request.Cookies["Car-Trading"]["Username"].ToString();
     DataSet ds = new DataSet();
     DatabaseHandler obj=new DatabaseHandler();
     ds = obj.GetSellerId(sellerUsername);
     String sellerId = ds.Tables[0].Rows[0]["SELLER_ID"].ToString();
     ds = obj.GetSellerCarStock(sellerId);
     GridView1.DataSource = ds;
     GridView1.DataBind();
 }