Code

//先创建数据适配器,

SqlDataAdapter da=new SqlDataAdapter();

da.SelectCommand=new SqlCommand(sql,conn);

//创建和填充数据集

DataSet ds=new DataSet();

da.Fill(ds,"Customers");

//每个查询返回一个数据集,每个结果都保存在单独的DataTable中.第一个显示地命名Customers，第二个表达默认名词为Customers1.

//从数据集的Tables属性获得DataTables对象集合

DataTableCollection dtc=ds.Tables;

在显示第一个表时:

string fl="country='Germany'";//sql where

string srt="CompanyName desc";//sql desc

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.SqlClient;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            SqlConnection conn = new SqlConnection("server=zhuobin;uid=sa;pwd=zhuobin;database=Northwind");
            string sql1 = @"select * from customers ";//Notice:add a space after the string sql1
            string sql2 = @"select * from products where unitprice<10";
            string sql = sql1 + sql2;
            try
            {
                
                SqlDataAdapter da = new SqlDataAdapter();
                da.SelectCommand = new SqlCommand(sql, conn);
                DataSet ds = new DataSet();

da.Fill(ds, "customers");
                //Console.WriteLine("I love you !");
                
                //get the table collections 
                DataTableCollection dtc = ds.Tables;//the tables collections of the ds
                //display data from the first table
                Console.WriteLine("Result from the customers tables:");
                
                Console.WriteLine("CompanyName".PadRight(20),"ContactName".PadRight(23)+"\n");
                //set display filter
                
                string fl = "country='Germany'";
                //set sort
                string srt = "Companyname";
                //display the filtered and sorted data
                foreach (DataRow row in dtc["customers"].Select(fl, srt))
                {
                    Console.WriteLine("{0}\t{1}",row["companyname"].ToString().PadRight(25),row["contactname"].ToString());
                }
                //display the data from the second table
                Console.WriteLine("\n-----------------------------------------------------");
                Console.WriteLine("The result from products :");
                Console.WriteLine("ProductName".PadRight(20),"UintPrice".PadRight(21));
                //display data
                foreach (DataRow row in dtc[1].Rows)
                {
                    Console.WriteLine("{0}\t{1}",row["productname"].ToString().PadRight(25),row["unitprice"].ToString());
                }
                
            }
            catch (SqlException ex)
            {
                Console.WriteLine("The error {0}", ex.Message);
            }
            finally
            {
                conn.Close();
            }
            Console.ReadLine();
        }
    }
}