string sConnectionString = "Data Source=localhost;Integrated Security=SSPI;Initial Catalog=Employee;";

using (SqlConnection conn = new SqlConnection(sConnectionString ))
{
  SqlCommand comd = conn.CreateCommand();
  comd .CommandText = "SELECT EmpId, EmpName FROM Employees";
  
  conn.Open();

  using (SqlDataReader dr = comd .ExecuteReader())
  {
    while (dr.Read())
      Console.WriteLine("{0}\t{1}", dr.GetString(0), dr.GetString(1));
  }
}