问从数据库中检索主键

EN

public partial class MainWindow : Window
{

System.Data.SqlClient.SqlConnection con;
System.Data.SqlClient.SqlDataAdapter da;

DataSet sessions;

public MainWindow()
{
    InitializeComponent();
}

private void button1_Click(object sender, RoutedEventArgs e)
{
    con = new System.Data.SqlClient.SqlConnection();

    sessions = new DataSet();

    con.ConnectionString = "Data Source=.\\SQLEXPRESS;AttachDbFilename=C:\\Users\\md\\PokerDataBase.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True";

    con.Open();

    string sql = "SELECT * From Sessions";
    da = new System.Data.SqlClient.SqlDataAdapter(sql, con);
    da.Fill(sessions, "Sessions");

    con.Close();

    System.Data.SqlClient.SqlCommandBuilder cb;
    cb = new System.Data.SqlClient.SqlCommandBuilder(da);

    DataTable dt = sessions.Tables["Sessions"];


    DataRow table = sessions.Tables["Sessions"].Rows[position];
    table[0] = "Some Data";
    table[1] = "Some Data";
    table[2] = "Some Data";
    table[3] = 2;
    table[4] = 3;
    sessions.Tables["Sessions"].Rows[2].Delete();
    sessions.Tables["Sessions"].Rows.InsertAt(table, 2);

    da.Update(sessions, "Sessions");
}
}