黑马程序员 DataSet离线数据集

using (SqlConnection conn = new SqlConnection("Data Source=.; Initial Catalog=MyTest;User ID=sa;Password=123456"))
            {
                conn.Open();
                using (SqlCommand cmd = conn.CreateCommand())
                {
                    cmd.CommandText = "select * from T_Student where Age<@aaa";
                    cmd.Parameters.Add(new SqlParameter("@aaa", 60));
                    //cmd.ExecuteReader(

                    //SqlDataAdapter是一个帮我们把SqlCommand查询结果填充到DataSet
                    //中的类
                    SqlDataAdapter adapter = new SqlDataAdapter(cmd);

                    //DataSet相当于本地的一个复杂集合（List<int>）
                    DataSet dataset = new DataSet();
                    adapter.Fill(dataset);//执行cmd并且把SqlCommand查询结果填充到DataSet

                    DataTable table = dataset.Tables[0];
                    DataRowCollection rows = table.Rows;
                    for (int i = 0; i < rows.Count; i++)
                    {
                        DataRow row = rows[i];
                        int age = (int)row["Age"];
                        string name = (string)row["Name"];
                        MessageBox.Show(name + "," + age);
                    }
                }
            }