写入cookie并取出

SqlDataAdapter sda = new SqlDataAdapter();
DataSet myds = new DataSet();
sda.Fill(myds, "tb_ter");
DataRowView mydrv =myds.Tables["tb_ter"].DefaultView[0];
string gra_de = Convert.ToString(mydrv.Row["Grade"]);
HttpCookie nc = new HttpCookie("newcookie");
nc.Values["Grade"] = gra_de;
Response.Cookies.Add(nc);
接收
HttpCookie getcookie = Request.Cookies["newcookie"];
string Gra_de = getcookie.Values["Grade"];