C#操作数据库

用DataSet方法读取数据

OracleHelper.cs

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

namespace TestOracleOperation
{
    class OracleHelper
    {
        private OracleConnection connection = null;

        private void OpenDB(string connStr)
        {
            connection = new OracleConnection(connStr);

            if (connection.State == ConnectionState.Closed)
            {
                connection.Open();
            }
        }

        private void CloseDB()
        {
            if (connection != null && connection.State == ConnectionState.Open)
            {
                connection.Close();
                connection.Dispose();
            }
            
        }

        /// <summary>
/// 查询数据库 
/// </summary>
/// <param name="sqlStr">查询语句</param>
/// <param name="connStr">连接数据库</param>
/// <param name="tableName">存放DataTable对象的</param>
/// <returns></returns>
        public DataSet Query(string sqlStr, string connStr, string tableName)
        {
            DataSet dataSet = new DataSet();

            try
            {
                OpenDB(connStr);

                OracleCommand command = new OracleCommand(sqlStr, connection);

                OracleDataAdapter dataAdapter = new OracleDataAdapter(command);
               
                dataAdapter.Fill(dataSet, tableName);
            }
            finally 
            {
                CloseDB();
                Console.WriteLine(connection.State);
            }
           
            return dataSet;
        }
    }
}

Program.cs

using System;
using System.Data;

namespace TestOracleOperation
{
    class Program
    {
        static void Main(string[] args)
        {
            string conStr = "Data Source=testOracle;User Id=test;Password=test;";
            string sqlComm = "SELECT * FROM users where rownum<10";

            OracleHelper oracleHelper = new OracleHelper();

            DataSet accountSet = oracleHelper.Query(sqlComm, conStr, "users ");

            foreach (DataRow row in accountSet.Tables["users "].Rows)
            {
                Console.WriteLine(row["user_id"] + "\t" + row["user_passport"]);
            }

            Console.ReadKey();

        }
    }
}

参考：http://www.cnblogs.com/dongdonghuihui/archive/2009/08/13/1545446.html