ADO.NET中主要对象

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlClient;
using System.Configuration;
using System.Data;

namespace Demo_ADONET
{
    class Program
    {
        static void Main(string[] args)
        {
            string connectionString = "Data Source=(local);Initial Catalog=TestDatabase;User ID=sa;Password=123456";
            TestDataReader(connectionString);
            TestDataAdapterFill(connectionString);

            Console.ReadLine();
        }

        /// <summary>
        /// DataReader示例
        /// </summary>
        /// <param name="connString"></param>
        public static void TestDataReader(string connString)
        {
            string queryString = "SELECT ID,NAME,PRICR FROM TEST2 WHERE PRICR>=3";
            using (SqlConnection connection =
                    new SqlConnection(connString))
            {
                SqlCommand command = new SqlCommand(queryString, connection);

                try
                {
                    connection.Open();
                    SqlDataReader reader = command.ExecuteReader();
                    while (reader.Read())
                    {
                        Console.WriteLine(string.Format("ID{0};NAME{1};PRICE{2}", reader[0], reader[1], reader[2]));
                    }

                    connection.Close();
                }
                catch (Exception ex)
                {

                    Console.WriteLine(ex.Message);
                }
            }
        }

        /// <summary>
        /// 用户保存从数据源读取的数据
        /// </summary>
        private static DataSet dataSet = new DataSet();

        /// <summary>
        /// 通过DataAdapter从数据源读取数据并填充到DataSet中
        /// </summary>
        /// <param name="connString"></param>
        public static void TestDataAdapterFill(string connString)
        {
            using (SqlConnection conn = new SqlConnection(connString))
            {
                string queryString = "SELECT ID,NAME,PRICR FROM TEST2";
                try
                {
                    conn.Open();
                    SqlCommand command = new SqlCommand(queryString, conn);
                    //DataSet ds = new DataSet();
                    SqlDataAdapter adapter = new SqlDataAdapter(command);
                    adapter.Fill(dataSet);

                    if (dataSet != null && dataSet.Tables.Count > 0)
                    {
                        DataTable dataTable = dataSet.Tables[0];
                        for (int i = 0; i < dataTable.Rows.Count; i++)
                        {
                            Console.WriteLine("ID:{0};Name:{1};Price:{2}",
                                dataTable.Rows[i]["ID"], dataTable.Rows[i]["NAME"], dataTable.Rows[i]["PRICR"]);
                        }
                    }
                }
                catch (Exception ex)
                {

                    throw ex;
                }
                finally
                {
                    conn.Close();
                }
            }
        }
    }
}