OracleConnection conn = new OracleConnection();
                conn.ConnectionString = "Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=127.0.0.1)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=orcl)));Persist Security Info=True;User ID=scott;Password=12345;";
                conn.Open();
                OracleCommand cmd = conn.CreateCommand();
                cmd.CommandText = "select * from users where user_id=" + textBox4.Text;
                cmd.CommandType = CommandType.Text;
                OracleDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    textBox1.Text = reader["user_Name"].ToString();
                    textBox2.Text = reader["user_address"].ToString();
                    textBox3.Text = reader["user_wage"].ToString();
                }