ADO Net C# Tutorial

using System;
using System.Data;
using System.Data.SqlClient;
    class Program
    {
        static void Main(string[] args)
        {
            string sqlConnectString = "Data Source=(local);" +
                "Integrated security=SSPI;Initial Catalog=AdventureWorks;";
            string sqlSelect = "SELECT * FROM Person.Contact";
            string sqlSelectEmpty = "SELECT * FROM Person.Contact";
            SqlDataAdapter da = new SqlDataAdapter(sqlSelect, sqlConnectString);
            DataTable dt = new DataTable( );
            da.Fill(dt);
            Console.WriteLine("DataTable has records = {0}", dt.Rows.Count > 0);
            using (SqlConnection connection = new SqlConnection(sqlConnectString))
            {
                SqlCommand command = new SqlCommand(sqlSelect, connection);
                connection.Open( );
                SqlDataReader dr = command.ExecuteReader( );
                Console.WriteLine(dr.HasRows);
                Console.WriteLine(dr.Read( ));
                dr.Close( );
            }
            da = new SqlDataAdapter(sqlSelectEmpty, sqlConnectString);
            dt = new DataTable( );
            da.Fill(dt);
        }
    }