Csharp/CSharp Tutorial/ADO.Net/DataTableCollection

Filter DataTableCollection: criteria and sort

using System;
using System.Data;
using System.Data.SqlClient;
class MainClass
{
   static void Main(string[] args)
   {
      string connString = @"server = .\sqlexpress;integrated security = true;database = northwind";
      string sql1 = @"select * from customers";
      string sql2 = @"select * from products where unitprice < 10";
      string sql = sql1 + sql2;
      SqlConnection conn = new SqlConnection(connString);
      try
      {
         SqlDataAdapter da = new SqlDataAdapter();
         da.SelectCommand = new SqlCommand(sql, conn);
         DataSet ds = new DataSet();
         da.Fill(ds, "customers");
         DataTableCollection dtc = ds.Tables;
         Console.WriteLine("CompanyName".PadRight(20) +"ContactName".PadLeft(23) + "\n");
         string fl = "country = "Germany"";
         string srt = "companyname asc";
         foreach (DataRow row in dtc["customers"].Select(fl, srt))
         {
           Console.WriteLine("{0}\t{1}",
              row["CompanyName"].ToString().PadRight(25),
              row["ContactName"]);
         }
         Console.WriteLine("ProductName".PadRight(20) +"UnitPrice".PadLeft(21));
         foreach (DataRow row in dtc[1].Rows)
         {
            Console.WriteLine("{0}\t{1}",
               row["productname"].ToString().PadRight(25),
               row["unitprice"]);
         }
      }
      catch(Exception e)
      {
         Console.WriteLine("Error: " + e);
      }
      finally
      {
         conn.Close();
      }
   }
}