using System;
using System.Data;
using System.Xml;
using System.Data.Common;
using System.Collections;

using Discuz.Config;
using Discuz.Common;
using Discuz.Common.Generic;

namespace Discuz.Data
{
    /// <summary>
    /// 数据访问助手类
    /// </summary>
    public partial class DbHelper
    {
        #region 私有变量

        /// <summary>
        /// 数据库连接字符串
        /// </summary>
        protected static string m_connectionstring = null;
        /// <summary>
        /// DbProviderFactory实例
        /// </summary>
        private static DbProviderFactory m_factory = null;
        /// <summary>
        /// Discuz!NT数据接口
        /// </summary>
        private static IDbProvider m_provider = null;
        /// <summary>
        /// 查询次数统计
        /// </summary>
        private static int m_querycount = 0;
        /// <summary>
        /// Parameters缓存哈希表
        /// </summary>
        private static Hashtable m_paramcache = Hashtable.Synchronized(new Hashtable());
        private static object lockHelper = new object();

        #endregion

#if DEBUG                      
        private static string m_querydetail = "";
        public static string QueryDetail
        {
            get { return m_querydetail; }
            set { m_querydetail = value; }
        }
        private static string GetQueryDetail(string commandText, DateTime dtStart, DateTime dtEnd, DbParameter[] cmdParams)
        {
            string tr = "<tr style=\"background: rgb(255, 255, 255) none repeat scroll 0%; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial;\">";
            string colums = "";
            string dbtypes = "";
            string values = "";
            string paramdetails = "";
            if (cmdParams != null && cmdParams.Length > 0)
            {
                foreach(DbParameter param in cmdParams)
                {
                    if (param == null)
                    {
                        continue;
                    }

                    colums += "<td>" + param.ParameterName + "</td>";
                    dbtypes += "<td>" + param.DbType.ToString() + "</td>";
                    values += "<td>" + param.Value.ToString() + "</td>";
                }
                paramdetails = string.Format("<table width=\"100%\" cellspacing=\"1\" cellpadding=\"0\" style=\"background: rgb(255, 255, 255) none repeat scroll 0%; margin-top: 5px; font-size: 12px; display: block; -moz-background-clip: -moz-initial; -moz-background-origin: -moz-initial; -moz-background-inline-policy: -moz-initial;\">{0}{1}</tr>{0}{2}</tr>{0}{3}</tr></table>", tr, colums, dbtypes, values);
            }
            return string.Format("<center><div style=\"border: 1px solid black; background:#FFF; margin: 2px; padding: 1em; text-align: left; width: 96%; clear: both;\"><div style=\"font-size: 12px; float: right; width: 100px; margin-bottom: 5px;\"><b>TIME:</b> {0}</div><span style=\"font-size: 12px;\">{1}{2}</span></div><br /></center>", dtEnd.Subtract(dtStart).TotalMilliseconds / 1000, commandText, paramdetails);
        }
#endif

        #region 属性

        /// <summary>
        /// 查询次数统计
        /// </summary>
        public static int QueryCount
        {
            get { return m_querycount; }
            set { m_querycount = value; }
        }

        /// <summary>
        /// 数据库连接字符串
        /// </summary>
        public static string ConnectionString
        {
            get
            {
                if (m_connectionstring == null)
                {
                    m_connectionstring = BaseConfigs.GetDBConnectString;
                }
                return m_connectionstring;
            }
            set
            {
                m_connectionstring = value;
            }
        }

        /// <summary>
        /// IDbProvider接口
        /// </summary>
        public static IDbProvider Provider
        {
            get
            {
                if (m_provider == null)
                {
                    lock (lockHelper)
                    {
                        if (m_provider == null)
                        {
                            try
                            {
                                m_provider = (IDbProvider)Activator.CreateInstance(Type.GetType(string.Format("Discuz.Data.{0}Provider, Discuz.Data.{0}", BaseConfigs.GetDbType), false, true));
                            }
                            catch
                            {
                                throw new Exception("请检查DNT.config中Dbtype节点数据库类型是否正确，例如：SqlServer、Access、MySql");
                            }
                        }
                    }
                }
                return m_provider;
            }
        }

        /// <summary>
        /// DbFactory实例
        /// </summary>
        public static DbProviderFactory Factory
        {
            get
            {
                if (m_factory == null)
                {
                    m_factory = Provider.Instance();
                }
                return m_factory;
            }
        }

        /// <summary>
        /// 刷新数据库提供者
        /// </summary>
        public static void ResetDbProvider()
        {
            BaseConfigs.ResetRealConfig();
            DatabaseProvider.ResetDbProvider();
            m_connectionstring = null;
            m_factory = null;
            m_provider = null;
        }

        #endregion

        #region 私有方法

        /// <summary>
        /// 将DbParameter参数数组(参数值)分配给DbCommand命令.
        /// 这个方法将给任何一个参数分配DBNull.Value;
        /// 该操作将阻止默认值的使用.
        /// </summary>
        /// <param name="command">命令名</param>
        /// <param name="commandParameters">DbParameters数组</param>
        private static void AttachParameters(DbCommand command, DbParameter[] commandParameters)
        {
            if (command == null) throw new ArgumentNullException("command");
            if (commandParameters != null)
            {
                foreach (DbParameter p in commandParameters)
                {
                    if (p != null)
                    {
                        // 检查未分配值的输出参数,将其分配以DBNull.Value.
                        if ((p.Direction == ParameterDirection.InputOutput || p.Direction == ParameterDirection.Input) &&
                            (p.Value == null))
                        {
                            p.Value = DBNull.Value;
                        }
                        command.Parameters.Add(p);
                    }
                }
            }
        }

        /// <summary>
        /// 将DataRow类型的列值分配到DbParameter参数数组.
        /// </summary>
        /// <param name="commandParameters">要分配值的DbParameter参数数组</param>
        /// <param name="dataRow">将要分配给存储过程参数的DataRow</param>
        private static void AssignParameterValues(DbParameter[] commandParameters, DataRow dataRow)
        {
            if ((commandParameters == null) || (dataRow == null))
                return;

            int i = 0;
            // 设置参数值
            foreach (DbParameter commandParameter in commandParameters)
            {
                // 创建参数名称,如果不存在,只抛出一个异常.
                if (commandParameter.ParameterName == null ||
                    commandParameter.ParameterName.Length <= 1)
                    throw new Exception(
                        string.Format("请提供参数{0}一个有效的名称{1}.", i, commandParameter.ParameterName));
                // 从dataRow的表中获取为参数数组中数组名称的列的索引.
                // 如果存在和参数名称相同的列,则将列值赋给当前名称的参数.
                if (dataRow.Table.Columns.IndexOf(commandParameter.ParameterName.Substring(1)) != -1)
                    commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
                i++;
            }
        }

        /// <summary>
        /// 将一个对象数组分配给DbParameter参数数组.
        /// </summary>
        /// <param name="commandParameters">要分配值的DbParameter参数数组</param>
        /// <param name="parameterValues">将要分配给存储过程参数的对象数组</param>
        private static void AssignParameterValues(DbParameter[] commandParameters, object[] parameterValues)
        {
            if ((commandParameters == null) || (parameterValues == null))
                return;

            // 确保对象数组个数与参数个数匹配,如果不匹配,抛出一个异常.
            if (commandParameters.Length != parameterValues.Length)
                throw new ArgumentException("参数值个数与参数不匹配.");

            // 给参数赋值
            for (int i = 0, j = commandParameters.Length; i < j; i++)
            {
                // If the current array value derives from IDbDataParameter, then assign its Value property
                if (parameterValues[i] is IDbDataParameter)
                {
                    IDbDataParameter paramInstance = (IDbDataParameter)parameterValues[i];
                    if (paramInstance.Value == null)
                        commandParameters[i].Value = DBNull.Value;
                    else
                        commandParameters[i].Value = paramInstance.Value;
                }
                else if (parameterValues[i] == null)
                    commandParameters[i].Value = DBNull.Value;
                else
                    commandParameters[i].Value = parameterValues[i];
            }
        }

        /// <summary>
        /// 预处理用户提供的命令,数据库连接/事务/命令类型/参数
        /// </summary>
        /// <param name="command">要处理的DbCommand</param>
        /// <param name="connection">数据库连接</param>
        /// <param name="transaction">一个有效的事务或者是null值</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param name="commandText">存储过程名或都SQL命令文本</param>
        /// <param name="commandParameters">和命令相关联的DbParameter参数数组,如果没有参数为'null'</param>
        /// <param name="mustCloseConnection"><c>true</c> 如果连接是打开的,则为true,其它情况下为false.</param>
        private static void PrepareCommand(DbCommand command, DbConnection connection, DbTransaction transaction, CommandType commandType, string commandText, DbParameter[] commandParameters, out bool mustCloseConnection)
        {
            if (command == null) throw new ArgumentNullException("command");
            if (commandText == null || commandText.Length == 0) throw new ArgumentNullException("commandText");

            // If the provided connection is not open, we will open it
            if (connection.State != ConnectionState.Open)
            {
                mustCloseConnection = true;
                connection.Open();
            }
            else
            {
                mustCloseConnection = false;
            }

            // 给命令分配一个数据库连接.
            command.Connection = connection;
            // 设置命令文本(存储过程名或SQL语句)
            command.CommandText = commandText;

            // 分配事务
            if (transaction != null)
            {
                if (transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
                command.Transaction = transaction;
            }

            // 设置命令类型.
            command.CommandType = commandType;

            // 分配命令参数
            if (commandParameters != null)
                AttachParameters(command, commandParameters);

            return;
        }

        /// <summary>
        /// 探索运行时的存储过程,返回DbParameter参数数组.
        /// 初始化参数值为 DBNull.Value.
        /// </summary>
        /// <param name="connection">一个有效的数据库连接</param>
        /// <param name="spName">存储过程名称</param>
        /// <param name="includeReturnValueParameter">是否包含返回值参数</param>
        /// <returns>返回DbParameter参数数组</returns>
        private static DbParameter[] DiscoverSpParameterSet(DbConnection connection, string spName, bool includeReturnValueParameter)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            if (connection.State == ConnectionState.Open)
                connection.Close();

            connection.ConnectionString = GetRealConnectionString(spName, CommandType.StoredProcedure);
            connection.Open();

            DbCommand cmd = connection.CreateCommand();
            cmd.CommandText = spName;
            cmd.CommandType = CommandType.StoredProcedure;            
            
            // 检索cmd指定的存储过程的参数信息,并填充到cmd的Parameters参数集中.
            Provider.DeriveParameters(cmd);
            connection.Close();
            // 如果不包含返回值参数,将参数集中的每一个参数删除.
            if (!includeReturnValueParameter)
                cmd.Parameters.RemoveAt(0);

            // 创建参数数组
            DbParameter[] discoveredParameters = new DbParameter[cmd.Parameters.Count];
            // 将cmd的Parameters参数集复制到discoveredParameters数组.
            cmd.Parameters.CopyTo(discoveredParameters, 0);

            // 初始化参数值为 DBNull.Value.
            foreach (DbParameter discoveredParameter in discoveredParameters)
            {
                discoveredParameter.Value = DBNull.Value;
            }
            return discoveredParameters;
        }

        /// <summary>
        /// DbParameter参数数组的深层拷贝.
        /// </summary>
        /// <param name="originalParameters">原始参数数组</param>
        /// <returns>返回一个同样的参数数组</returns>
        private static DbParameter[] CloneParameters(DbParameter[] originalParameters)
        {
            DbParameter[] clonedParameters = new DbParameter[originalParameters.Length];

            for (int i = 0, j = originalParameters.Length; i < j; i++)
            {
                clonedParameters[i] = (DbParameter)((ICloneable)originalParameters[i]).Clone();
            }

            return clonedParameters;
        }

        #endregion 私有方法结束

        #region ExecuteNonQuery方法

        /// <summary>
        /// 执行指定连接字符串,类型的DbCommand.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery("SELECT * FROM [table123]");
        /// </remarks>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQuery(string commandText)
        {
            return ExecuteNonQuery(CommandType.Text, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定连接字符串,类型的DbCommand.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery("SELECT * FROM [table123]");
        /// </remarks>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQuery(out int id, string commandText)
        {
            return ExecuteNonQuery(out id, CommandType.Text, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定连接字符串,类型的DbCommand.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQuery(CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定连接字符串,并返回刚插入的自增ID
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQuery(out int id, CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(out id, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定连接字符串,类型的DbCommand.如果没有提供参数,不返回结果.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">DbParameter参数数组</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQuery(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");

            using (DbConnection connection = Factory.CreateConnection())
            {
                connection.ConnectionString = GetRealConnectionString(commandText, commandType);//ConnectionString;
                //connection.Open();

                return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
            }
        }

     
        /// <summary>
        /// 执行指定连接字符串并返回刚插入的自增ID,类型的DbCommand.如果没有提供参数,不返回结果.
        /// </summary>
        /// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">DbParameter参数数组</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQuery(out int id, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");

            using (DbConnection connection = Factory.CreateConnection())
            {
                connection.ConnectionString = GetRealConnectionString(commandText, commandType);//ConnectionString;
                //connection.Open();

                return ExecuteNonQuery(out id, connection, commandType, commandText, commandParameters);
            }
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令 
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(DbConnection connection, CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(connection, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令并返回自增ID 
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(out int id, DbConnection connection, CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(out id, connection, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">T存储过程名称或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(DbConnection connection, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (connection == null) throw new ArgumentNullException("connection");

            // 创建DbCommand命令,并进行预处理
            DbCommand cmd = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (DbTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);

#if DEBUG
            DateTime dt1 = DateTime.Now;
#endif
            // 执行DbCommand命令,并返回结果.
            int retval = cmd.ExecuteNonQuery();
#if DEBUG
            DateTime dt2 = DateTime.Now;
            m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
            m_querycount++;
#endif

            // 清除参数,以便再次使用.
            cmd.Parameters.Clear();
            if (mustCloseConnection)
                connection.Close();
            return retval;
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">T存储过程名称或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(out int id, DbConnection connection, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (Provider.GetLastIdSql().Trim() == "") throw new ArgumentNullException("GetLastIdSql is \"\"");

            // 创建DbCommand命令,并进行预处理
            DbCommand cmd = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (DbTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);

            // 执行命令
            int retval = cmd.ExecuteNonQuery();
            // 清除参数,以便再次使用.
            cmd.Parameters.Clear();
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = Provider.GetLastIdSql();

#if DEBUG                
            DateTime dt1 = DateTime.Now;
#endif
            id = TypeConverter.ObjectToInt(cmd.ExecuteScalar());
#if DEBUG                
            DateTime dt2 = DateTime.Now;

            m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
#endif
            m_querycount++;


            if (mustCloseConnection)
            {
                connection.Close();
            }
            return retval;
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令,将对象数组的值赋给存储过程参数.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值
        /// 示例:  
        ///  int result = ExecuteNonQuery(conn, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(DbConnection connection, string spName, params object[] parameterValues)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            // 如果有参数值
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // 从缓存中加载存储过程参数
                DbParameter[] commandParameters = GetSpParameterSet(connection, spName);

                // 给存储过程分配参数值
                AssignParameterValues(commandParameters, parameterValues);

                return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// 执行带事务的DbCommand.
        /// </summary>
        /// <remarks>
        /// 示例.:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="transaction">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回影响的行数/returns>
        public static int ExecuteNonQuery(DbTransaction transaction, CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(transaction, commandType, commandText, (DbParameter[])null);
        }


        /// <summary>
        /// 执行带事务的DbCommand.
        /// </summary>
        /// <remarks>
        /// 示例.:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="transaction">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回影响的行数/returns>
        public static int ExecuteNonQuery(out int id, DbTransaction transaction, CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(out id, transaction, commandType, commandText, (DbParameter[])null);
        }


        /// <summary>
        /// 执行带事务的DbCommand(指定参数).
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="transaction">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(DbTransaction transaction, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");

            // 预处理
            DbCommand cmd = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);

            // 执行
#if DEBUG
            DateTime dt1 = DateTime.Now;
#endif
            // 执行DbCommand命令,并返回结果.
            int retval = cmd.ExecuteNonQuery();
#if DEBUG
            DateTime dt2 = DateTime.Now;
            m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
            m_querycount++;
#endif

            // 清除参数集,以便再次使用.
            cmd.Parameters.Clear();
            return retval;
        }

        /// <summary>
        /// 执行带事务的DbCommand(指定参数).
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="transaction">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(out int id, DbTransaction transaction, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");

            // 预处理
            DbCommand cmd = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);

            // 执行
            int retval = cmd.ExecuteNonQuery();
            // 清除参数,以便再次使用.
            cmd.Parameters.Clear();
            cmd.CommandType = CommandType.Text;
            cmd.CommandText = Provider.GetLastIdSql();
            id = TypeConverter.ObjectToInt(cmd.ExecuteScalar().ToString());
            return retval;
        }

        /// <summary>
        /// 执行带事务的DbCommand(指定参数值).
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值
        /// 示例:  
        ///  int result = ExecuteNonQuery(conn, trans, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="transaction">一个有效的数据库连接对象</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回受影响的行数</returns>
        public static int ExecuteNonQuery(DbTransaction transaction, string spName, params object[] parameterValues)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            // 如果有参数值
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // 从缓存中加载存储过程参数,如果缓存中不存在则从数据库中检索参数信息并加载到缓存中. ()
                DbParameter[] commandParameters = GetSpParameterSet(transaction.Connection, spName);

                // 给存储过程参数赋值
                AssignParameterValues(commandParameters, parameterValues);

                // 调用重载方法
                return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数值
                return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName);
            }
        }

        #endregion ExecuteNonQuery方法结束

        #region ExecuteCommandWithSplitter方法
        /// <summary>
        /// 运行含有GO命令的多条SQL命令
        /// </summary>
        /// <param name="commandText">SQL命令字符串</param>
        /// <param name="splitter">分割字符串</param>
        public static void ExecuteCommandWithSplitter(string commandText, string splitter)
        {
            int startPos = 0;

            do
            {
                int lastPos = commandText.IndexOf(splitter, startPos);
                int len = (lastPos > startPos ? lastPos : commandText.Length) - startPos;
                string query = commandText.Substring(startPos, len);

                if (query.Trim().Length > 0)
                {
                    try
                    {
                        ExecuteNonQuery(CommandType.Text, query);
                    }
                    catch { ;}
                }

                if (lastPos == -1)
                    break;
                else
                    startPos = lastPos + splitter.Length;
            } while (startPos < commandText.Length);

        }

        /// <summary>
        /// 运行含有GO命令的多条SQL命令
        /// </summary>
        /// <param name="commandText">SQL命令字符串</param>
        public static void ExecuteCommandWithSplitter(string commandText)
        {
            ExecuteCommandWithSplitter(commandText, "\r\nGO\r\n");
        }
        #endregion ExecuteCommandWithSplitter方法结束

        #region ExecuteDataset方法


        /// <summary>
        /// 执行指定数据库连接字符串的命令,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset("SELECT * FROM [table1]");
        /// </remarks>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(string commandText)
        {
            return ExecuteDataset(CommandType.Text, commandText, (DbParameter[])null);
        }


        /// <summary>
        /// 执行指定数据库连接字符串的命令,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(CommandType commandType, string commandText)
        {
            return ExecuteDataset(commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库连接字符串的命令,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 示例: 
        ///  DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">SqlParamters参数数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");

            // 创建并打开数据库连接对象,操作完成释放对象.

            using (DbConnection connection = Factory.CreateConnection())
            {
                connection.ConnectionString = ConnectionString;
                // connection.Open();

                // 调用指定数据库连接字符串重载方法.
                return ExecuteDataset(connection, commandType, commandText, commandParameters);
            }
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(DbConnection connection, CommandType commandType, string commandText)
        {
            return ExecuteDataset(connection, commandType, commandText, (DbParameter[])null);
        }


        /// <summary>
        /// 执行指定数据库连接对象的命令,指定存储过程参数,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(DbConnection connection, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            // connection.Close();

            connection.ConnectionString = GetRealConnectionString(commandText, commandType);
            connection.Open();
            // 预处理
            DbCommand cmd = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (DbTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);

            // 创建DbDataAdapter和DataSet.
            using (DbDataAdapter da = Factory.CreateDataAdapter())
            {
                da.SelectCommand = cmd;
                DataSet ds = new DataSet();

#if DEBUG                
               DateTime dt1 = DateTime.Now;
#endif
                // 填充DataSet.
                da.Fill(ds);
#if DEBUG                
                DateTime dt2 = DateTime.Now;

                m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
#endif
                m_querycount++;

                cmd.Parameters.Clear();

                if (mustCloseConnection)
                    connection.Close();

                return ds;
            }
        }

     
        /// <summary>
        /// 执行指定数据库连接对象的命令,指定参数值,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输入参数和返回值.
        /// 示例.:  
        ///  DataSet ds = ExecuteDataset(conn, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(DbConnection connection, string spName, params object[] parameterValues)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // 比缓存中加载存储过程参数
                DbParameter[] commandParameters = GetSpParameterSet(connection, spName);

                // 给存储过程参数分配值
                AssignParameterValues(commandParameters, parameterValues);

                return ExecuteDataset(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return ExecuteDataset(connection, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// 执行指定事务的命令,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="transaction">事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(DbTransaction transaction, CommandType commandType, string commandText)
        {
            return ExecuteDataset(transaction, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定事务的命令,指定参数,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="transaction">事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(DbTransaction transaction, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");

            // 预处理
            DbCommand cmd = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);

            // 创建 DataAdapter & DataSet
            using (DbDataAdapter da = Factory.CreateDataAdapter())
            {
                da.SelectCommand = cmd;
                DataSet ds = new DataSet();
                da.Fill(ds);
                cmd.Parameters.Clear();
                return ds;
            }
        }

        /// <summary>
        /// 执行指定事务的命令,指定参数值,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输入参数和返回值.
        /// 示例.:  
        ///  DataSet ds = ExecuteDataset(trans, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="transaction">事务</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(DbTransaction transaction, string spName, params object[] parameterValues)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // 从缓存中加载存储过程参数
                DbParameter[] commandParameters = GetSpParameterSet(transaction.Connection, spName);

                // 给存储过程参数分配值
                AssignParameterValues(commandParameters, parameterValues);

                return ExecuteDataset(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return ExecuteDataset(transaction, CommandType.StoredProcedure, spName);
            }
        }

        #endregion ExecuteDataset数据集命令结束

        #region ExecuteReader 数据阅读器

        /// <summary>
        /// 枚举,标识数据库连接是由BaseDbHelper提供还是由调用者提供
        /// </summary>
        private enum DbConnectionOwnership
        {
            /// <summary>由BaseDbHelper提供连接</summary>
            Internal,
            /// <summary>由调用者提供连接</summary>
            External
        }

        /// <summary>
        /// 执行指定数据库连接对象的数据阅读器.
        /// </summary>
        /// <remarks>
        /// 如果是BaseDbHelper打开连接,当连接关闭DataReader也将关闭.
        /// 如果是调用都打开连接,DataReader由调用都管理.
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="transaction">一个有效的事务,或者为 'null'</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <param name="commandParameters">DbParameters参数数组,如果没有参数则为'null'</param>
        /// <param name="connectionOwnership">标识数据库连接对象是由调用者提供还是由BaseDbHelper提供</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        private static DbDataReader ExecuteReader(DbConnection connection, DbTransaction transaction, CommandType commandType, string commandText, DbParameter[] commandParameters, DbConnectionOwnership connectionOwnership)
        {
            if (connection == null) throw new ArgumentNullException("connection");

            //connection.Close();
            connection.ConnectionString = GetRealConnectionString(commandText, commandType);
            connection.Open();

            bool mustCloseConnection = false;
            // 创建命令
            DbCommand cmd = Factory.CreateCommand();
            try
            {
                PrepareCommand(cmd, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);

                // 创建数据阅读器
                DbDataReader dataReader;

#if DEBUG                
                DateTime dt1 = DateTime.Now;
#endif
                if (connectionOwnership == DbConnectionOwnership.External)
                {
                    dataReader = cmd.ExecuteReader();
                }
                else
                {
                    dataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                }
#if DEBUG                
                DateTime dt2 = DateTime.Now;

                m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
#endif
                m_querycount++;
                // 清除参数,以便再次使用..
                bool canClear = true;
                foreach (DbParameter commandParameter in cmd.Parameters)
                {
                    if (commandParameter.Direction != ParameterDirection.Input)
                        canClear = false;
                }

                if (canClear)
                {
                    //cmd.Dispose();
                    cmd.Parameters.Clear();
                }

                return dataReader;
            }
            catch
            {
                if (mustCloseConnection)
                    connection.Close();
                throw;
            }
        }


      
        /// <summary>
        /// 执行指定数据库连接字符串的数据阅读器.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(CommandType commandType, string commandText)
        {
            return ExecuteReader(commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库连接字符串的数据阅读器,指定参数.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组(new DbParameter("@prodid", 24))</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
            DbConnection connection = null;
            try
            {
                connection = Factory.CreateConnection();
                connection.ConnectionString = ConnectionString;
                //connection.Open();

                return ExecuteReader(connection, null, commandType, commandText, commandParameters, DbConnectionOwnership.Internal);
            }
            catch
            {
                // If we fail to return the SqlDatReader, we need to close the connection ourselves
                if (connection != null) connection.Close();
                throw;
            }
        }

        /// <summary>
        /// 执行指定数据库连接字符串的数据阅读器,指定参数值.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(connString, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(string spName, params object[] parameterValues)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                DbParameter[] commandParameters = GetSpParameterSet(spName);

                AssignParameterValues(commandParameters, parameterValues);

                return ExecuteReader(ConnectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return ExecuteReader(ConnectionString, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// 执行指定数据库连接对象的数据阅读器.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(DbConnection connection, CommandType commandType, string commandText)
        {
            return ExecuteReader(connection, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// [调用者方式]执行指定数据库连接对象的数据阅读器,指定参数.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(DbConnection connection, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            return ExecuteReader(connection, (DbTransaction)null, commandType, commandText, commandParameters, DbConnectionOwnership.External);
        }

        /// <summary>
        /// [调用者方式]执行指定数据库连接对象的数据阅读器,指定参数值.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(conn, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="spName">T存储过程名</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(DbConnection connection, string spName, params object[] parameterValues)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                DbParameter[] commandParameters = GetSpParameterSet(connection, spName);

                AssignParameterValues(commandParameters, parameterValues);

                return ExecuteReader(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return ExecuteReader(connection, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// [调用者方式]执行指定数据库事务的数据阅读器,指定参数值.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(trans, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(DbTransaction transaction, CommandType commandType, string commandText)
        {
            return ExecuteReader(transaction, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// [调用者方式]执行指定数据库事务的数据阅读器,指定参数.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///   DbDataReader dr = ExecuteReader(trans, CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(DbTransaction transaction, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");

            return ExecuteReader(transaction.Connection, transaction, commandType, commandText, commandParameters, DbConnectionOwnership.External);
        }

        /// <summary>
        /// [调用者方式]执行指定数据库事务的数据阅读器,指定参数值.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 
        /// 示例:  
        ///  DbDataReader dr = ExecuteReader(trans, "GetOrders", 24, 36);
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="spName">存储过程名称</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReader(DbTransaction transaction, string spName, params object[] parameterValues)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            // 如果有参数值
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                DbParameter[] commandParameters = GetSpParameterSet(transaction.Connection, spName);

                AssignParameterValues(commandParameters, parameterValues);

                return ExecuteReader(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数值
                return ExecuteReader(transaction, CommandType.StoredProcedure, spName);
            }
        }

        #endregion ExecuteReader数据阅读器

        #region ExecuteScalar 返回结果集中的第一行第一列

        /// <summary>
        /// 执行指定数据库连接字符串的命令,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(connString, CommandType.StoredProcedure, "GetOrderCount");
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteScalar(commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库连接字符串的命令,指定参数,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(connString, CommandType.StoredProcedure, "GetOrderCount", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
            // 创建并打开数据库连接对象,操作完成释放对象.
            using (DbConnection connection = Factory.CreateConnection())
            {
                connection.ConnectionString = ConnectionString;
                // connection.Open();

                // 调用指定数据库连接字符串重载方法.
                return ExecuteScalar(connection, commandType, commandText, commandParameters);
            }
        }

      
        /// <summary>
        /// 执行指定数据库连接对象的命令,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(conn, CommandType.StoredProcedure, "GetOrderCount");
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(DbConnection connection, CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteScalar(connection, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令,指定参数,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(conn, CommandType.StoredProcedure, "GetOrderCount", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(DbConnection connection, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (connection == null) throw new ArgumentNullException("connection");

            //connection.Close();
            connection.ConnectionString = GetRealConnectionString(commandText, commandType);
            connection.Open();

            // 创建DbCommand命令,并进行预处理
            DbCommand cmd = Factory.CreateCommand();

            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (DbTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);

            // 执行DbCommand命令,并返回结果.
            object retval = cmd.ExecuteScalar();

            // 清除参数,以便再次使用.
            cmd.Parameters.Clear();

            if (mustCloseConnection)
                connection.Close();

            return retval;
        }

      
        /// <summary>
        /// 执行指定数据库连接对象的命令,指定参数值,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(conn, "GetOrderCount", 24, 36);
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="spName">存储过程名称</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(DbConnection connection, string spName, params object[] parameterValues)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            // 如果有参数值
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // 从缓存中加载存储过程参数,如果缓存中不存在则从数据库中检索参数信息并加载到缓存中. ()
                DbParameter[] commandParameters = GetSpParameterSet(connection, spName);

                // 给存储过程参数赋值
                AssignParameterValues(commandParameters, parameterValues);

                // 调用重载方法
                return ExecuteScalar(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数值
                return ExecuteScalar(connection, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// 执行指定数据库事务的命令,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(trans, CommandType.StoredProcedure, "GetOrderCount");
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(DbTransaction transaction, CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteScalar(transaction, commandType, commandText, (DbParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库事务的命令,指定参数,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(trans, CommandType.StoredProcedure, "GetOrderCount", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(DbTransaction transaction, CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");

            // 创建DbCommand命令,并进行预处理
            DbCommand cmd = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);

#if DEBUG                
            DateTime dt1 = DateTime.Now;
#endif
            // 执行DbCommand命令,并返回结果.
            object retval = cmd.ExecuteScalar();
#if DEBUG                
            DateTime dt2 = DateTime.Now;
            m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
#endif
            m_querycount++;
            // 清除参数,以便再次使用.
            cmd.Parameters.Clear();
            return retval;
        }

        /// <summary>
        /// 执行指定数据库事务的命令,指定参数值,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(trans, "GetOrderCount", 24, 36);
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="spName">存储过程名称</param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(DbTransaction transaction, string spName, params object[] parameterValues)
        {
            if (transaction == null) throw new ArgumentNullException("transaction");
            if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            // 如果有参数值
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // PPull the parameters for this stored procedure from the parameter cache ()
                DbParameter[] commandParameters = GetSpParameterSet(transaction.Connection, spName);

                // 给存储过程参数赋值
                AssignParameterValues(commandParameters, parameterValues);

                // 调用重载方法
                return ExecuteScalar(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数值
                return ExecuteScalar(transaction, CommandType.StoredProcedure, spName);
            }
        }

        #endregion ExecuteScalar

        #region FillDataset 填充数据集
        /// <summary>
        /// 执行指定数据库连接字符串的命令,映射数据表并填充数据集.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  FillDataset(connString, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"});
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)</param>
        //public static void FillDataset(CommandType commandType, string commandText, DataSet dataSet, string[] tableNames)
        //{
        //    if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
        //    if (dataSet == null) throw new ArgumentNullException("dataSet");

        //    // 创建并打开数据库连接对象,操作完成释放对象.
        //    using (DbConnection connection = Factory.CreateConnection())
        //    {
        //        connection.ConnectionString = ConnectionString;
        //        connection.Open();

        //        // 调用指定数据库连接字符串重载方法.
        //        FillDataset(connection, commandType, commandText, dataSet, tableNames);
        //    }
        //}

        /// <summary>
        /// 执行指定数据库连接字符串的命令,映射数据表并填充数据集.指定命令参数.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  FillDataset(connString, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"}, new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>
        //public static void FillDataset(CommandType commandType, string commandText, DataSet dataSet, string[] tableNames, params DbParameter[] commandParameters)
        //{
        //    if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
        //    if (dataSet == null) throw new ArgumentNullException("dataSet");
        //    // 创建并打开数据库连接对象,操作完成释放对象.
        //    using (DbConnection connection = Factory.CreateConnection())
        //    {
        //        connection.ConnectionString = ConnectionString;
        //        connection.Open();

        //        // 调用指定数据库连接字符串重载方法.
        //        FillDataset(connection, commandType, commandText, dataSet, tableNames, commandParameters);
        //    }
        //}

        /// <summary>
        /// 执行指定数据库连接字符串的命令,映射数据表并填充数据集,指定存储过程参数值.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 
        /// 示例:  
        ///  FillDataset(connString, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"}, 24);
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符串</param>
        /// <param name="spName">存储过程名称</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>    
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        //public static void FillDataset(string spName, DataSet dataSet, string[] tableNames, params object[] parameterValues)
        //{
        //    if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
        //    if (dataSet == null) throw new ArgumentNullException("dataSet");
        //    // 创建并打开数据库连接对象,操作完成释放对象.
        //    using (DbConnection connection = Factory.CreateConnection())
        //    {
        //        connection.ConnectionString = ConnectionString;
        //        connection.Open();

        //        // 调用指定数据库连接字符串重载方法.
        //        FillDataset(connection, spName, dataSet, tableNames, parameterValues);
        //    }
        //}

        /// <summary>
        /// 执行指定数据库连接对象的命令,映射数据表并填充数据集.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  FillDataset(conn, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"});
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>    
        public static void FillDataset(DbConnection connection, CommandType commandType, string commandText, DataSet dataSet, string[] tableNames)
        {
            FillDataset(connection, commandType, commandText, dataSet, tableNames, null);
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令,映射数据表并填充数据集,指定参数.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  FillDataset(conn, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"}, new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        public static void FillDataset(DbConnection connection, CommandType commandType, string commandText, DataSet dataSet, string[] tableNames, params DbParameter[] commandParameters)
        {
            FillDataset(connection, null, commandType, commandText, dataSet, tableNames, commandParameters);
        }

        /// <summary>
        /// 执行指定数据库连接对象的命令,映射数据表并填充数据集,指定存储过程参数值.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 
        /// 示例:  
        ///  FillDataset(conn, "GetOrders", ds, new string[] {"orders"}, 24, 36);
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="spName">存储过程名称</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        //public static void FillDataset(DbConnection connection, string spName, DataSet dataSet, string[] tableNames, params object[] parameterValues)
        //{
        //    if (connection == null) throw new ArgumentNullException("connection");
        //    if (dataSet == null) throw new ArgumentNullException("dataSet");
        //    if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

        //    // 如果有参数值
        //    if ((parameterValues != null) && (parameterValues.Length > 0))
        //    {
        //        // 从缓存中加载存储过程参数,如果缓存中不存在则从数据库中检索参数信息并加载到缓存中. ()
        //        DbParameter[] commandParameters = GetSpParameterSet(connection, spName);

        //        // 给存储过程参数赋值
        //        AssignParameterValues(commandParameters, parameterValues);

        //        // 调用重载方法
        //        FillDataset(connection, CommandType.StoredProcedure, spName, dataSet, tableNames, commandParameters);
        //    }
        //    else
        //    {
        //        // 没有参数值
        //        FillDataset(connection, CommandType.StoredProcedure, spName, dataSet, tableNames);
        //    }
        //}

        /// <summary>
        /// 执行指定数据库事务的命令,映射数据表并填充数据集.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  FillDataset(trans, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"});
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>
        //public static void FillDataset(DbTransaction transaction, CommandType commandType, string commandText, DataSet dataSet, string[] tableNames)
        //{
        //    FillDataset(transaction, commandType, commandText, dataSet, tableNames, null);
        //}

        /// <summary>
        /// 执行指定数据库事务的命令,映射数据表并填充数据集,指定参数.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  FillDataset(trans, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"}, new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        public static void FillDataset(DbTransaction transaction, CommandType commandType, string commandText, DataSet dataSet, string[] tableNames, params DbParameter[] commandParameters)
        {
            FillDataset(transaction.Connection, transaction, commandType, commandText, dataSet, tableNames, commandParameters);
        }

        /// <summary>
        /// 执行指定数据库事务的命令,映射数据表并填充数据集,指定存储过程参数值.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值参数.
        /// 
        /// 示例:  
        ///  FillDataset(trans, "GetOrders", ds, new string[]{"orders"}, 24, 36);
        /// </remarks>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="spName">存储过程名称</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>
        /// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
        //public static void FillDataset(DbTransaction transaction, string spName, DataSet dataSet, string[] tableNames, params object[] parameterValues)
        //{
        //    if (transaction == null) throw new ArgumentNullException("transaction");
        //    if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
        //    if (dataSet == null) throw new ArgumentNullException("dataSet");
        //    if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

        //    // 如果有参数值
        //    if ((parameterValues != null) && (parameterValues.Length > 0))
        //    {
        //        // 从缓存中加载存储过程参数,如果缓存中不存在则从数据库中检索参数信息并加载到缓存中. ()
        //        DbParameter[] commandParameters = GetSpParameterSet(transaction.Connection, spName);

        //        // 给存储过程参数赋值
        //        AssignParameterValues(commandParameters, parameterValues);

        //        // 调用重载方法
        //        FillDataset(transaction, CommandType.StoredProcedure, spName, dataSet, tableNames, commandParameters);
        //    }
        //    else
        //    {
        //        // 没有参数值
        //        FillDataset(transaction, CommandType.StoredProcedure, spName, dataSet, tableNames);
        //    }
        //}

        /// <summary>
        /// [私有方法][内部调用]执行指定数据库连接对象/事务的命令,映射数据表并填充数据集,DataSet/TableNames/DbParameters.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  FillDataset(conn, trans, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"}, new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="transaction">一个有效的连接事务</param>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="dataSet">要填充结果集的DataSet实例</param>
        /// <param name="tableNames">表映射的数据表数组
        /// 用户定义的表名 (可有是实际的表名.)
        /// </param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        private static void FillDataset(DbConnection connection, DbTransaction transaction, CommandType commandType, string commandText, DataSet dataSet, string[] tableNames, params DbParameter[] commandParameters)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (dataSet == null) throw new ArgumentNullException("dataSet");

            // 创建DbCommand命令,并进行预处理
            DbCommand command = Factory.CreateCommand();
            bool mustCloseConnection = false;
            PrepareCommand(command, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);

            // 执行命令
            using (DbDataAdapter dataAdapter = Factory.CreateDataAdapter())
            {
                dataAdapter.SelectCommand = command;
                // 追加表映射
                if (tableNames != null && tableNames.Length > 0)
                {
                    string tableName = "Table";
                    for (int index = 0; index < tableNames.Length; index++)
                    {
                        if (tableNames[index] == null || tableNames[index].Length == 0) throw new ArgumentException("The tableNames parameter must contain a list of tables, a value was provided as null or empty string.", "tableNames");
                        dataAdapter.TableMappings.Add(tableName, tableNames[index]);
                        tableName += (index + 1).ToString();
                    }
                }

                // 填充数据集使用默认表名称
                dataAdapter.Fill(dataSet);

                // 清除参数,以便再次使用.
                command.Parameters.Clear();
            }

            if (mustCloseConnection)
                connection.Close();
        }
        #endregion
       

        #region 检索指定的存储过程的参数集

        /// <summary>
        /// 返回指定的存储过程的参数集
        /// </summary>
        /// <remarks>
        /// 这个方法将查询数据库,并将信息存储到缓存.
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符</param>
        /// <param name="spName">存储过程名</param>
        /// <returns>返回DbParameter参数数组</returns>
        public static DbParameter[] GetSpParameterSet(string spName)
        {
            return GetSpParameterSet(spName, false);
        }

        /// <summary>
        /// 返回指定的存储过程的参数集
        /// </summary>
        /// <remarks>
        /// 这个方法将查询数据库,并将信息存储到缓存.
        /// </remarks>
        /// <param name="ConnectionString">一个有效的数据库连接字符.</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="includeReturnValueParameter">是否包含返回值参数</param>
        /// <returns>返回DbParameter参数数组</returns>
        public static DbParameter[] GetSpParameterSet(string spName, bool includeReturnValueParameter)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            using (DbConnection connection = Factory.CreateConnection())
            {
                connection.ConnectionString = ConnectionString;
                return GetSpParameterSetInternal(connection, spName, includeReturnValueParameter);
            }
        }

        /// <summary>
        /// [内部]返回指定的存储过程的参数集(使用连接对象).
        /// </summary>
        /// <remarks>
        /// 这个方法将查询数据库,并将信息存储到缓存.
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接字符</param>
        /// <param name="spName">存储过程名</param>
        /// <returns>返回DbParameter参数数组</returns>
        internal static DbParameter[] GetSpParameterSet(DbConnection connection, string spName)
        {
            return GetSpParameterSet(connection, spName, false);
        }

        /// <summary>
        /// [内部]返回指定的存储过程的参数集(使用连接对象)
        /// </summary>
        /// <remarks>
        /// 这个方法将查询数据库,并将信息存储到缓存.
        /// </remarks>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="includeReturnValueParameter">
        /// 是否包含返回值参数
        /// </param>
        /// <returns>返回DbParameter参数数组</returns>
        internal static DbParameter[] GetSpParameterSet(DbConnection connection, string spName, bool includeReturnValueParameter)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            using (DbConnection clonedConnection = (DbConnection)((ICloneable)connection).Clone())
            {
                return GetSpParameterSetInternal(clonedConnection, spName, includeReturnValueParameter);
            }
        }

        /// <summary>
        /// [私有]返回指定的存储过程的参数集(使用连接对象)
        /// </summary>
        /// <param name="connection">一个有效的数据库连接对象</param>
        /// <param name="spName">存储过程名</param>
        /// <param name="includeReturnValueParameter">是否包含返回值参数</param>
        /// <returns>返回DbParameter参数数组</returns>
        private static DbParameter[] GetSpParameterSetInternal(DbConnection connection, string spName, bool includeReturnValueParameter)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            string hashKey = connection.ConnectionString + ":" + spName + (includeReturnValueParameter ? ":include ReturnValue Parameter" : "");

            DbParameter[] cachedParameters;

            cachedParameters = m_paramcache[hashKey] as DbParameter[];
            if (cachedParameters == null)
            {
                DbParameter[] spParameters = DiscoverSpParameterSet(connection, spName, includeReturnValueParameter);
                m_paramcache[hashKey] = spParameters;
                cachedParameters = spParameters;
            }

            return CloneParameters(cachedParameters);
        }

        #endregion 参数集检索结束

        #region 生成参数

        public static DbParameter MakeInParam(string ParamName, DbType DbType, int Size, object Value)
        {
            return MakeParam(ParamName, DbType, Size, ParameterDirection.Input, Value);
        }

        public static DbParameter MakeOutParam(string ParamName, DbType DbType, int Size)
        {
            return MakeParam(ParamName, DbType, Size, ParameterDirection.Output, null);
        }

        public static DbParameter MakeParam(string ParamName, DbType DbType, Int32 Size, ParameterDirection Direction, object Value)
        {
            DbParameter param;

            param = Provider.MakeParam(ParamName, DbType, Size);

            param.Direction = Direction;
            if (!(Direction == ParameterDirection.Output && Value == null))
                param.Value = Value;

            return param;
        }

        #endregion 生成参数结束

        #region 执行ExecuteScalar,将结果以字符串类型输出。

        public static string ExecuteScalarToStr(CommandType commandType, string commandText)
        {
            object ec = ExecuteScalar(commandType, commandText);
            if (ec == null)
            {
                return "";
            }
            return ec.ToString();
        }


        public static string ExecuteScalarToStr(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            object ec = ExecuteScalar(commandType, commandText, commandParameters);
            if (ec == null)
            {
                return "";
            }
            return ec.ToString();
        }
        #endregion


        #region 下面的区域方法主要用于读写分离环境下使用
        /// <summary>
        /// 在主数据库中执行指定连接字符串,类型的DbCommand.如果没有提供参数,不返回结果.
        /// (注:主数据库链接即为DNT.config文件中Dbconnectstring的链接地址)
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQueryInMasterDB(CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQueryInMasterDB(CommandType commandType, string commandText)
        {
            return ExecuteNonQueryInMasterDB(commandType, commandText, null);
        }

        /// <summary>
        /// 在主数据库中执行指定连接字符串,类型的DbCommand.如果没有提供参数,不返回结果.
        /// (注:主数据库链接即为DNT.config文件中Dbconnectstring的链接地址)
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int result = ExecuteNonQuery(CommandType.StoredProcedure, "PublishOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">DbParameter参数数组</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQueryInMasterDB(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");

            using (DbConnection connection = Factory.CreateConnection())
            {
                connection.ConnectionString = ConnectionString;
                //connection.Open();

                return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
            }
        }

        /// <summary>
        /// 在主数据库中执行指定数据库连接对象的命令,指定存储过程参数,返回DataSet.
        /// (注:主数据库链接即为DNT.config文件中Dbconnectstring的链接地址)
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset(CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDatasetInMasterDB(CommandType commandType, string commandText)
        {
            return ExecuteDatasetInMasterDB(commandType, commandText, null);
        }

        /// <summary>
        /// 在主数据库中执行指定数据库连接对象的命令,指定存储过程参数,返回DataSet.
        /// (注:主数据库链接即为DNT.config文件中Dbconnectstring的链接地址)
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  DataSet ds = ExecuteDataset(CommandType.StoredProcedure, "GetOrders", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDatasetInMasterDB(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");

            // 创建并打开数据库连接对象,操作完成释放对象.
            using (DbConnection connection = Factory.CreateConnection())
            {
                if (connection == null) throw new ArgumentNullException("connection");

                connection.ConnectionString = ConnectionString;
                connection.Open();

                // 预处理
                DbCommand cmd = Factory.CreateCommand();
                bool mustCloseConnection = false;
                PrepareCommand(cmd, connection, (DbTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);

                // 创建DbDataAdapter和DataSet.
                using (DbDataAdapter da = Factory.CreateDataAdapter())
                {
                    da.SelectCommand = cmd;
                    DataSet ds = new DataSet();

#if DEBUG                
               DateTime dt1 = DateTime.Now;
#endif
                    // 填充DataSet.
                    da.Fill(ds);
#if DEBUG                
                DateTime dt2 = DateTime.Now;

                m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
#endif
                    m_querycount++;

                    cmd.Parameters.Clear();

                    if (mustCloseConnection)
                        connection.Close();

                    return ds;
                }
            }
        }


        /// <summary>
        /// 在主数据库中执行指定数据库连接对象的数据阅读器.(注:主数据库链接即为DNT.config文件中Dbconnectstring的链接地址)
        /// </summary>
        /// <remarks>
        /// 如果是BaseDbHelper打开连接,当连接关闭DataReader也将关闭.
        /// 如果是调用都打开连接,DataReader由调用都管理.
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReaderInMasterDB(CommandType commandType, string commandText)
        {
            return ExecuteReaderInMasterDB(commandType, commandText, null);
        }

        /// <summary>
        /// 在主数据库中执行指定数据库连接对象的数据阅读器.(注:主数据库链接即为DNT.config文件中Dbconnectstring的链接地址)
        /// </summary>
        /// <remarks>
        /// 如果是BaseDbHelper打开连接,当连接关闭DataReader也将关闭.
        /// 如果是调用都打开连接,DataReader由调用都管理.
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名或SQL语句</param>
        /// <param name="commandParameters">DbParameters参数数组,如果没有参数则为'null'</param>
        /// <returns>返回包含结果集的DbDataReader</returns>
        public static DbDataReader ExecuteReaderInMasterDB(CommandType commandType, string commandText, DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
            DbConnection connection = null;
            try
            {
                connection = Factory.CreateConnection();

                if (connection == null) throw new ArgumentNullException("connection");

                connection.ConnectionString = ConnectionString;
                connection.Open();

                bool mustCloseConnection = false;
                // 创建命令
                DbCommand cmd = Factory.CreateCommand();
                try
                {
                    PrepareCommand(cmd, connection, null, commandType, commandText, commandParameters, out mustCloseConnection);

                    // 创建数据阅读器
                    DbDataReader dataReader;

#if DEBUG                
                DateTime dt1 = DateTime.Now;
#endif
                    dataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);

#if DEBUG                
                DateTime dt2 = DateTime.Now;

                m_querydetail += GetQueryDetail(cmd.CommandText, dt1, dt2, commandParameters);
#endif
                    m_querycount++;
                    // 清除参数,以便再次使用..
                    bool canClear = true;
                    foreach (DbParameter commandParameter in cmd.Parameters)
                    {
                        if (commandParameter.Direction != ParameterDirection.Input)
                            canClear = false;
                    }

                    if (canClear)
                    {
                        //cmd.Dispose();
                        cmd.Parameters.Clear();
                    }

                    return dataReader;
                }
                catch
                {
                    if (mustCloseConnection)
                        connection.Close();
                    throw;
                }
            }
            catch
            {
                // If we fail to return the SqlDatReader, we need to close the connection ourselves
                if (connection != null) connection.Close();
                throw;
            }
        }


        /// <summary>
        /// 在主数据库中执行指定数据库连接对象的命令,指定参数,返回结果集中的第一行第一列.
        /// (注:主数据库链接即为DNT.config文件中Dbconnectstring的链接地址)
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(conn, CommandType.StoredProcedure, "GetOrderCount", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalarInMasterDB(CommandType commandType, string commandText)
        {
            return ExecuteScalarInMasterDB(commandType, commandText, null);
        }

        /// <summary>
        /// 在主数据库中执行指定数据库连接对象的命令,指定参数,返回结果集中的第一行第一列.
        /// </summary>
        /// <remarks>
        /// 示例:  
        ///  int orderCount = (int)ExecuteScalar(conn, CommandType.StoredProcedure, "GetOrderCount", new DbParameter("@prodid", 24));
        /// </remarks>
        /// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
        /// <param name="commandText">存储过程名称或SQL语句</param>
        /// <param name="commandParameters">分配给命令的SqlParamter参数数组</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalarInMasterDB(CommandType commandType, string commandText, params DbParameter[] commandParameters)
        {
            if (ConnectionString == null || ConnectionString.Length == 0) throw new ArgumentNullException("ConnectionString");
            // 创建并打开数据库连接对象,操作完成释放对象.
            using (DbConnection connection = Factory.CreateConnection())
            {
                if (connection == null) throw new ArgumentNullException("connection");

                connection.ConnectionString = ConnectionString;
                connection.Open();

                // 创建DbCommand命令,并进行预处理
                DbCommand cmd = Factory.CreateCommand();

                bool mustCloseConnection = false;
                PrepareCommand(cmd, connection, (DbTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);

                // 执行DbCommand命令,并返回结果.
                object retval = cmd.ExecuteScalar();

                // 清除参数,以便再次使用.
                cmd.Parameters.Clear();

                if (mustCloseConnection)
                    connection.Close();

                return retval;
            }
        }

        /// <summary>
        /// 是否使用快照数据库
        /// </summary>
        /// <param name="commandText">查询</param>
        /// <returns></returns>
        private static bool UserSnapDatabase(string commandText)
        {
            // 如果上次刷新cookie间隔小于5分钟, 则不刷新数据库最后活动时间
            if (commandText.StartsWith(BaseConfigs.GetTablePrefix + "create"))
            {
                Utils.WriteCookie("JumpAfterWrite", Environment.TickCount.ToString());
                return false;
            }
            else if (!String.IsNullOrEmpty(Utils.GetCookie("JumpAfterWrite")) && (Environment.TickCount - TypeConverter.StrToInt(Utils.GetCookie("JumpAfterWrite"), Environment.TickCount)) < DbSnapConfigs.GetConfig().WriteWaitTime * 1000)
                return false;
            else if (!commandText.StartsWith(BaseConfigs.GetTablePrefix + "get"))
                return false;

            return true;
        }

    
        /// <summary>
        /// 获取使用的数据库(或快照)链接串
        /// </summary>
        /// <param name="commandText">存储过程名或都SQL命令文本</param>
        /// <returns></returns>
        public static string GetRealConnectionString(string commandText, CommandType commandType)
        {
            //当在线表被布署到别的数据库时
            if (EntLibConfigs.GetConfig() != null)
            {
                OnlineTableConnect onlineTableConnect = EntLibConfigs.GetConfig().Onlinetableconnect;
                if (onlineTableConnect.Enable && !string.IsNullOrEmpty(onlineTableConnect.SqlServerConn))
                {
                    if ((commandType == CommandType.Text && commandText.IndexOf(BaseConfigs.GetTablePrefix + "online]") > 0) ||
                        (commandType == CommandType.StoredProcedure && commandText.IndexOf("online") > 0))
                    {
                        return EntLibConfigs.GetConfig().Onlinetableconnect.SqlServerConn;
                    }
                }
            }           
            //使用读写分离方案时
            if (DbSnapConfigs.GetConfig() != null && DbSnapConfigs.GetConfig().AppDbSnap)
            {
                commandText = commandText.Trim().ToLower();
                if (commandText.StartsWith("select") || ((commandText.StartsWith(BaseConfigs.GetTablePrefix) && UserSnapDatabase(commandText))))
                {
                    DbSnapInfo dbSnapInfo = GetLoadBalanceScheduling.GetConnectDbSnap();

                    if (DbSnapConfigs.GetConfig().RecordeLog && snapLogList.Capacity > snapLogList.Count)
                        snapLogList.Add(string.Format("{{'SouceID' : {0}, 'DbconnectString' : '{1}', 'CommandText' : '{2}', 'PostDateTime' : '{3}'}},",
                                         dbSnapInfo.SouceID,
                                         dbSnapInfo.DbconnectString,
                                         commandText.Replace("'",""),
                                         Discuz.Common.Utils.GetDateTime()));

                    return dbSnapInfo.DbconnectString;
                }
            }

            return ConnectionString;
        }

        /// <summary>
        /// 快照日志数据
        /// </summary>
        private static List<string> snapLogList = new List<string>(400);

        /// <summary>
        /// 获取数据快照JSON数据
        /// </summary>
        /// <returns></returns>
        public static string GetSnapLogJson()
        {
            string snapLogJson = "";
            foreach (string snapLog in snapLogList)
            {
                snapLogJson += snapLog;
            }

            return "[" + snapLogJson.Trim(',') + "]";
        }

        /// <summary>
        /// 清空数据快照JSON数据
        /// </summary>
        public static void ClearSnapLogJson()
        {
            snapLogList = new List<string>(400);
        }

        /// <summary>
        /// 负载均衡调度接口
        /// </summary>
        private static ILoadBalanceScheduling m_loadBalanceSche;
        /// <summary>
        /// 初始化负载均衡调度接口实例
        /// </summary>
        private static ILoadBalanceScheduling GetLoadBalanceScheduling
        {
            get
            {
                if (m_loadBalanceSche == null)
                {
                    try
                    {
                        m_loadBalanceSche = (ILoadBalanceScheduling)Activator.CreateInstance(Type.GetType(string.Format("Discuz.EntLib.{0}, Discuz.EntLib", DbSnapConfigs.GetConfig().LoadBalanceScheduling), false, true));
                    }
                    catch
                    {
                        throw new Exception("请检查config/dbsnap.config中配置是否正确");
                    }
                }
                return m_loadBalanceSche;
            }
        }
        #endregion
    }
}