DbProviderFactory f = DbProviderFactories.GetFactory(System.Configuration.ConfigurationManager.ConnectionStrings["ado"].ProviderName);DbConnection conn = f.CreateConnection();            conn.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["ado"].ConnectionString;conn.Open();DbCommand cmd = f.CreateCommand();cmd.CommandText = "select * from student";cmd.Connection = conn;DbDataReader re = cmd.ExecuteReader();while (re.Read()){    int id = (int)re["StuId"];    string name = (string)re["StuName"];    int age = (int)re["StuAge"];    ListViewItem item = new ListViewItem();    item.Text = id.ToString();    item.SubItems.Add(        new ListViewItem.ListViewSubItem { Text = name }        );    item.SubItems.Add(        new ListViewItem.ListViewSubItem { Text = age.ToString() }        );    listView1.Items.Add(item);}re.Close();conn.Close();