DBHelper,ADO直接操作数据库，扩展DataTable操作数据裤的方法

本人测试通过的直接通过ADO访问数据库的持久层代码，针对微软的数据库。

using System;
using System.Data;
using System.Data.Common;
using System.Configuration;

namespace DBTool
{
    public class DbHelper
    {
        private static string dbProviderName = ConfigurationManager.AppSettings["DbHelperProvider"];
        private static string dbConnectionString = ConfigurationManager.AppSettings["DbHelperConnectionString"];

        private DbConnection connection;
        public DbHelper()
        {
            this.connection = CreateConnection(DbHelper.dbConnectionString);
        }
        public DbHelper(string connectionString)
        {
            this.connection = CreateConnection(connectionString);
        }
        public static DbConnection CreateConnection()
        {
            DbProviderFactory dbfactory = DbProviderFactories.GetFactory(DbHelper.dbProviderName);
            DbConnection dbconn = dbfactory.CreateConnection();
            dbconn.ConnectionString = DbHelper.dbConnectionString;
            return dbconn;
        }
        public static DbConnection CreateConnection(string connectionString)
        {
            DbProviderFactory dbfactory = DbProviderFactories.GetFactory(DbHelper.dbProviderName);
            DbConnection dbconn = dbfactory.CreateConnection();
            dbconn.ConnectionString = connectionString;
            return dbconn;
        }

        public DbCommand GetStoredProcCommond(string storedProcedure)
        {
            DbCommand dbCommand = connection.CreateCommand();
            dbCommand.CommandText = storedProcedure;
            dbCommand.CommandType = CommandType.StoredProcedure;
            return dbCommand;
        }
        public DbCommand GetSqlStringCommond(string sqlQuery)
        {
            DbCommand dbCommand = connection.CreateCommand();
            dbCommand.CommandText = sqlQuery;
            dbCommand.CommandType = CommandType.Text;
            return dbCommand;
        }

        //增加参数
        #region 增加参数
        public void AddParameterCollection(DbCommand cmd, DbParameterCollection dbParameterCollection)
        {
            foreach (DbParameter dbParameter in dbParameterCollection)
            {
                cmd.Parameters.Add(dbParameter);
            }
        }
        public void AddOutParameter(DbCommand cmd, string parameterName, DbType dbType, int size)
        {
            DbParameter dbParameter = cmd.CreateParameter();
            dbParameter.DbType = dbType;
            dbParameter.ParameterName = parameterName;
            dbParameter.Size = size;
            dbParameter.Direction = ParameterDirection.Output;
            cmd.Parameters.Add(dbParameter);
        }
        public void AddInParameter(DbCommand cmd, string parameterName, DbType dbType, object value)
        {
            DbParameter dbParameter = cmd.CreateParameter();
            dbParameter.DbType = dbType;
            dbParameter.ParameterName = parameterName;
            dbParameter.Value = value;
            dbParameter.Direction = ParameterDirection.Input;
            cmd.Parameters.Add(dbParameter);
        }
        public void AddReturnParameter(DbCommand cmd, string parameterName, DbType dbType)
        {
            DbParameter dbParameter = cmd.CreateParameter();
            dbParameter.DbType = dbType;
            dbParameter.ParameterName = parameterName;
            dbParameter.Direction = ParameterDirection.ReturnValue;
            cmd.Parameters.Add(dbParameter);
        }
        public DbParameter GetParameter(DbCommand cmd, string parameterName)
        {
            return cmd.Parameters[parameterName];
        }

        #endregion


        #region 执行事物
        public DataSet ExecuteDataSet(DbCommand cmd)
        {
            DbProviderFactory dbfactory = DbProviderFactories.GetFactory(DbHelper.dbProviderName);
            DbDataAdapter dbDataAdapter = dbfactory.CreateDataAdapter();
            dbDataAdapter.SelectCommand = cmd;
            DataSet ds = new DataSet();
            dbDataAdapter.Fill(ds);
            return ds;
        }

        public DataTable ExecuteDataTable(DbCommand cmd)
        {
            DbProviderFactory dbfactory = DbProviderFactories.GetFactory(DbHelper.dbProviderName);
            DbDataAdapter dbDataAdapter = dbfactory.CreateDataAdapter();
            dbDataAdapter.SelectCommand = cmd;
            DataTable dataTable = new DataTable();
            dbDataAdapter.Fill(dataTable);
            return dataTable;
        }

        public DbDataReader ExecuteReader(DbCommand cmd)
        {
            cmd.Connection.Open();
            DbDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
            return reader;
        }
        public int ExecuteNonQuery(DbCommand cmd)
        {
            cmd.Connection.Open();
            int ret = cmd.ExecuteNonQuery();
            cmd.Connection.Close();
            return ret;
        }

        public object ExecuteScalar(DbCommand cmd)
        {
            cmd.Connection.Open();
            object ret = cmd.ExecuteScalar();
            cmd.Connection.Close();
            return ret;
        }
        #endregion


        #region 执行
        public DataSet ExecuteDataSet(DbCommand cmd, Trans t)
        {
            cmd.Connection = t.DbConnection;
            cmd.Transaction = t.DbTrans;
            DbProviderFactory dbfactory = DbProviderFactories.GetFactory(DbHelper.dbProviderName);
            DbDataAdapter dbDataAdapter = dbfactory.CreateDataAdapter();
            dbDataAdapter.SelectCommand = cmd;
            DataSet ds = new DataSet();
            dbDataAdapter.Fill(ds);
            return ds;
        }

        public DataTable ExecuteDataTable(DbCommand cmd, Trans t)
        {
            cmd.Connection = t.DbConnection;
            cmd.Transaction = t.DbTrans;
            DbProviderFactory dbfactory = DbProviderFactories.GetFactory(DbHelper.dbProviderName);
            DbDataAdapter dbDataAdapter = dbfactory.CreateDataAdapter();
            dbDataAdapter.SelectCommand = cmd;
            DataTable dataTable = new DataTable();
            dbDataAdapter.Fill(dataTable);
            return dataTable;
        }

        public DbDataReader ExecuteReader(DbCommand cmd, Trans t)
        {
            cmd.Connection.Close();
            cmd.Connection = t.DbConnection;
            cmd.Transaction = t.DbTrans;
            DbDataReader reader = cmd.ExecuteReader();
            DataTable dt = new DataTable();
            return reader;
        }
        public int ExecuteNonQuery(DbCommand cmd, Trans t)
        {
            cmd.Connection.Close();
            cmd.Connection = t.DbConnection;
            cmd.Transaction = t.DbTrans;
            int ret = cmd.ExecuteNonQuery();
            return ret;
        }

        public object ExecuteScalar(DbCommand cmd, Trans t)
        {
            cmd.Connection.Close();
            cmd.Connection = t.DbConnection;
            cmd.Transaction = t.DbTrans;
            object ret = cmd.ExecuteScalar();
            return ret;
        }
        #endregion
    }

    public class Trans : IDisposable
    {
        private DbConnection conn;
        private DbTransaction dbTrans;
        public DbConnection DbConnection
        {
            get { return this.conn; }
        }
        public DbTransaction DbTrans
        {
            get { return this.dbTrans; }
        }

        public Trans()
        {
            conn = DbHelper.CreateConnection();
            conn.Open();
            dbTrans = conn.BeginTransaction();
        }
        public Trans(string connectionString)
        {
            conn = DbHelper.CreateConnection(connectionString);
            conn.Open();
            dbTrans = conn.BeginTransaction();
        }
        public void Commit()
        {
            dbTrans.Commit();
            this.Colse();
        }

        public void RollBack()
        {
            dbTrans.Rollback();
            this.Colse();
        }

        public void Dispose()
        {
            this.Colse();
        }

        public void Colse()
        {
            if (conn.State == System.Data.ConnectionState.Open)
            {
                conn.Close();
            }
        }
    }
}

源码（包括测试）下载

直接使用dll文件，测试的代码

using System;
using System.Collections.Generic;
using System.Text;
using System.Data.Common;
using System.Data;


namespace DBTool
{
    public class Program
    {
        /// <summary>
        /// 执行DcreateDb.sql直接来创建数据库的结构和数据
        /// 记得要添加对WithDB的引用。
        /// </summary>
        /// <param name="args"></param>
        public static void Main(string[] args)
        {
            DataTable table = new DataTable();
            table = table.UseDb_Select("select * from t");

        }

        #region 事?物?处鋦理え?

        public static void DoBusiness()
        {
            using (Trans t = new Trans())
            {
                try
                {
                    D1(t);
                    throw new Exception();//如果有异常会自动回滚
                    D2(t);
                    t.Commit();
                }
                catch
                {
                    t.RollBack();
                }
            }
        }

        public static void D1(Trans t)
        {
            DbHelper db = new DbHelper();
            DbCommand cmd = db.GetStoredProcCommond("t2_insert");
            db.AddInParameter(cmd, "@timeticks", DbType.Int64, DateTime.Now.Ticks);
            db.AddOutParameter(cmd, "@outString", DbType.String, 20);
            db.AddReturnParameter(cmd, "@returnValue", DbType.Int32);

            if (t == null) db.ExecuteNonQuery(cmd);
            else db.ExecuteNonQuery(cmd, t);

            string s = db.GetParameter(cmd, "@outString").Value as string;//out parameter
            int r = Convert.ToInt32(db.GetParameter(cmd, "@returnValue").Value);//return value
        }
        public static void D2(Trans t)
        {
            DbHelper db = new DbHelper();
            DbCommand cmd = db.GetSqlStringCommond("insert t1 (id)values('..')");
            if (t == null) db.ExecuteNonQuery(cmd);
            else db.ExecuteNonQuery(cmd, t);
        }
        #endregion

        /// <summary>
        /// DataReader使用
        /// </summary>
        private static void DataReaderUser()
        {
            DbHelper db = new DbHelper();
            DbCommand cmd = db.GetStoredProcCommond("t2_insert");
            db.AddInParameter(cmd, "@timeticks", DbType.Int64, DateTime.Now.Ticks);
            db.AddOutParameter(cmd, "@outString", DbType.String, 20);
            db.AddReturnParameter(cmd, "@returnValue", DbType.Int32);

            DataTable dt = new DataTable();

            using (DbDataReader reader = db.ExecuteReader(cmd))
            {
                dt.Load(reader);
            }
            string s = db.GetParameter(cmd, "@outString").Value as string;//out parameter
            int r = Convert.ToInt32(db.GetParameter(cmd, "@returnValue").Value);//return value
        }

        /// <summary>
        /// 输入参数/输出参数/返回值
        /// </summary>
        private static void RunIOParameter()
        {
            DbHelper db = new DbHelper();
            DbCommand cmd = db.GetStoredProcCommond("t2_insert");
            db.AddInParameter(cmd, "@timeticks", DbType.Int64, DateTime.Now.Ticks);
            db.AddOutParameter(cmd, "@outString", DbType.String, 20);
            db.AddReturnParameter(cmd, "@returnValue", DbType.Int32);

            db.ExecuteNonQuery(cmd);

            string s = db.GetParameter(cmd, "@outString").Value as string;//out parameter
            int r = Convert.ToInt32(db.GetParameter(cmd, "@returnValue").Value);//return value
        }

        /// <summary>
        /// 返回DataTable
        /// </summary>
        private static void ReturnDataTable()
        {
            DbHelper db = new DbHelper();
            DbCommand cmd = db.GetSqlStringCommond("t1_findall");
            DataTable dt = db.ExecuteDataTable(cmd);
        }

        /// <summary>
        /// 返回DataSet
        /// </summary>
        private static void ReturnDataSet()
        {
            DbHelper db = new DbHelper();
            DbCommand cmd = db.GetSqlStringCommond("select * from t1");
            DataSet ds = db.ExecuteDataSet(cmd);
        }

        /// <summary>
        /// 执行存储过程
        /// </summary>
        private static void RunStoredProc()
        {
            DbHelper db = new DbHelper();
            DbCommand cmd = db.GetStoredProcCommond("t1_insert");
            db.AddInParameter(cmd, "@id", System.Data.DbType.String, "heihei");
            db.ExecuteNonQuery(cmd);
        }

        /// <summary>
        /// 1.执行SQL语句
        /// </summary>
        private static void RunSQL()
        {
            DbHelper db = new DbHelper();
            System.Data.Common.DbCommand cmd = db.GetSqlStringCommond("insert t1 (id)values('haha')");
            db.ExecuteNonQuery(cmd);
        }
    }
}

ADO源代码以及测试  

测试库文件的代码

可执行文件