DataSet基本用法

using (SqlConnection conn = new SqlConnection("Data Source=.;Initial Catalog=HA;User Id=sa;Password=123"))            {                conn.Open();                using (SqlCommand cmd = conn.CreateCommand())                {                    cmd.CommandText = "select * from Table_1 where Age>@Age";                    cmd.Parameters.Add(new SqlParameter ("@Age",20));                    SqlDataAdapter adapter = new SqlDataAdapter(cmd);                    DataSet dataset = new DataSet();                    adapter.Fill(dataset);                    DataTable table = dataset.Tables[0];                    DataRowCollection rows = table.Rows;                    for (int i = 0; i < rows.Count; i++)                    {                        DataRow row = rows[i];                        string name = (string)row["Name"];                        int age=(int)row["Age"];                        string sex=(string)row["Sex"];                        MessageBox.Show(name+""+age.ToString ()+"   "+sex);                    }                }