string connectionString = "user id=Mytnii2;password=12345;" +
                       "data source=(DESCRIPTION=(ADDRESS=" +
                       "(PROTOCOL=tcp)(HOST=localhost)" +
                       "(PORT=1521))(CONNECT_DATA=" +
                       "(SERVICE_NAME=orcl)))";
            using (OracleConnection connection = new OracleConnection())
            {
                connection.ConnectionString = connectionString;
                try
                {
                    connection.Open();
                    DataSet ds = new DataSet();
                    DataTable dt = new DataTable("mytable1");
                    OracleCommand myCommand = connection.CreateCommand();
                    myCommand.CommandText = "select * from contracts_sec";

                    OracleDataReader reader = myCommand.ExecuteReader();
                    ds.Tables.Clear();
                    ds.Tables.Add(dt);
                    ds.Load(reader, LoadOption.PreserveChanges, ds.Tables[0]);
                    DataView view = new DataView(ds.Tables[0]);
                    // GridView2.DataBind();

                    GridView1.DataSource = view;
                    GridView1.DataBind();
                    
                }
                catch (Exception ex)
                {
                   

                }
            }