private void Form1_Load(object sender, EventArgs e)

        {

            dataGridView1.Columns.Add("col1", "empno");

            dataGridView1.Columns.Add("col2", "name");

            dataGridView1.Columns.Add("col3", "age");        

        }



        private void button1_Click(object sender, EventArgs e)

        {

            //连接字符串

            //string connectionString = "Data Source=orcl;User ID=system;Password=system;Unicode=True ";

            string connectionString = "Data Source=orcl;User ID=scott;Password=scott;Unicode=True";

            //创建Oracle连接对象

            OracleConnection con = new OracleConnection(connectionString);

            //打开连接

            con.Open();



            //建立Sql查询语句

            string sql = "select * from emp";

            //创建Oracle命令行对象

            OracleCommand cmd = new OracleCommand(sql, con);

            //执行命令行对象

            OracleDataReader odr = cmd.ExecuteReader(CommandBehavior.CloseConnection);

            IList<UserInfo> users = new List<UserInfo>();

            while (odr.Read())

            {

                UserInfo user = new UserInfo();

                user.UserID = Convert.ToInt32(odr["EMPNO"]);

                user.UserName = Convert.ToString(odr["ENAME"]);

                user.UserAge = Convert.ToString(odr["sal"]);

                users.Add(user);

            }

            //绑定DataGridView控件

            dataGridView1.DataSource = users;