微软官方的SQLHelper类(含完整中文注释)(转)

数据库操作类真的没有必要自己去写,因为成熟的类库真的非常完善了,拿来直接用就好,省时省力。

里面的函数一堆,常用的就那几个,无非就是增删改查嘛,来看下几种常用的函数:

1.ExecuteNonQuery 执行增删改
2.ExecuteReader 执行查询
3.ExecuteScalar 返回首行首列

使用方法介绍

Web.config配置

1 <connectionStrings>
2     <add name="ConnectionString" connectionString="server=127.0.0.1;uid=sa;pwd=ok;database=PetShop;Max Pool Size =512; Min Pool Size=0; Connection Lifetime = 300;packet size=1000;" providerName="System.Data.SqlClient" />
3 </connectionStrings>

调用函数的写法

1 sql = "UPDATE Student set Name = @Name WHERE Id = @Id";
2 SqlHelper.ExecuteNonQuery(CommandType.Text, sql, new SqlParameter[]{
3  new SqlParameter("@Name", name),
4  new SqlParameter("@Id", id)
5 });

这样调用就比较简化,而且比较灵活

using System;
using System.Data;
using System.Xml;
using System.Data.SqlClient;
using System.Collections;
namespace myhelper
{
    /// <summary>
    /// SqlServer数据访问帮助类
    /// </summary>
    public sealed class SqlHelper
    {
        #region 私有构造函数和方法
        private SqlHelper() {}
        /// <summary>
        /// 将SqlParameter参数数组(参数值)分配给SqlCommand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>SqlHelperSqlHelper
        /// <param>命令名</param>
        /// <param>SqlParameters数组</param>
        private static void AttachParameters(SqlCommand command, SqlParameter[] commandParameters)
        {
            if( command == null ) throw new ArgumentNullException( "command" );
            if( commandParameters != null )
            {
                foreach (SqlParameter 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SqlParameter参数数组.
        /// </summary>
        /// <param>要分配值的SqlParameter参数数组</param>
        /// <param>将要分配给存储过程参数的DataRow</param>
        private static void AssignParameterValues(SqlParameter[] commandParameters, DataRow dataRow)
        {
            if ((commandParameters == null) || (dataRow == null))
            {
                return;
            }
            int i = 0;
            // 设置参数值
            foreach(SqlParameter 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SqlParameter参数数组.
        /// </summary>
        /// <param>要分配值的SqlParameter参数数组</param>
        /// <param>将要分配给存储过程参数的对象数组</param>
        private static void AssignParameterValues(SqlParameter[] 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 is IDbDataParameter)
                {
                    IDbDataParameter paramInstance = (IDbDataParameter)parameterValues;
                    if( paramInstance.Value == null )
                    {
                        commandParameters.Value = DBNull.Value;
                    }
                    else
                    {
                        commandParameters.Value = paramInstance.Value;
                    }
                }
                else if (parameterValues == null)
                {
                    commandParameters.Value = DBNull.Value;
                }
                else
                {
                    commandParameters.Value = parameterValues;
                }
            }
        }

        /// <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>要处理的SqlCommand</param>
        /// <param>数据库连接</param>
        /// <param>一个有效的事务或者是null值</param>
        /// <param>命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param>存储过程名或都T-SQL命令文本</param>
        /// <param>和命令相关联的SqlParameter参数数组,如果没有参数为‘null‘</param>
        /// <param><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(SqlCommand command, SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] 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;
        }
        #endregion 私有构造函数和方法结束

        #region ExecuteNonQuery命令
        /// <summary>
        /// 执行指定连接字符串,类型的SqlCommand.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param>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 connectionString, CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(connectionString, commandType, commandText, (SqlParameter[])null);
        }

        /// <summary>
        /// 执行指定连接字符串,类型的SqlCommand.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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本, 其它.)</param>
        /// <param>存储过程名称或SQL语句</param>
        /// <param>SqlParameter参数数组</param>
        /// <returns>返回命令影响的行数</returns>
        public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
                return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
            }
        }

        /// <summary>
        /// 执行指定连接字符串的存储过程,将对象数组的值赋给存储过程参数,
        /// 此方法需要在参数缓存方法中探索参数并生成参数.
        /// </summary>
        /// <remarks>
        /// 这个方法没有提供访问输出参数和返回值.
        /// 示例:
        ///  int result = ExecuteNonQuery(connString, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param>一个有效的数据库连接字符串/param>
        /// <param>存储过程名称</param>
        /// <param>分配到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(string connectionString, 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" );
            // 如果存在参数值
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // 从探索存储过程参数(加载到缓存)并分配给存储过程参数数组.
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);
                // 给存储过程参数赋值
                AssignParameterValues(commandParameters, parameterValues);
                return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数情况下
                return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName);
            }
        }

        /// <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>一个有效的数据库连接对象</param>
        /// <param>命令类型(存储过程,命令文本或其它.)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(SqlConnection connection, CommandType commandType, string commandText)
        {
            return ExecuteNonQuery(connection, commandType, commandText, (SqlParameter[])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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型(存储过程,命令文本或其它.)</param>
        /// <param>T存储过程名称或T-SQL语句</param>
        /// <param>SqlParamter参数数组</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            // 创建SqlCommand命令,并进行预处理
            SqlCommand cmd = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );

            // Finally, execute the command
            int retval = cmd.ExecuteNonQuery();

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

        /// <summary>
        /// 执行带事务的SqlCommand(指定参数).
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型(存储过程,命令文本或其它.)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>SqlParamter参数数组</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQuery(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] 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
            SqlCommand cmd = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );

            // 执行
            int retval = cmd.ExecuteNonQuery();

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

        /// <summary>
        /// 执行带事务的SqlCommand(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>一个有效的数据库连接对象</param>
        /// <param>存储过程名</param>
        /// <param>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(SqlTransaction 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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.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 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(connString, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText)
        {
            return ExecuteDataset(connectionString, commandType, commandText, (SqlParameter[])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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>SqlParamters参数数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText, params SqlParameter[] 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 (SqlConnection connection = new SqlConnection(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字符串的命令,直接提供参数值,返回DataSet.
        /// </summary>
        /// <remarks>
        /// 此方法不提供访问存储过程输出参数和返回值.
        /// 示例:
        ///  DataSet ds = ExecuteDataset(connString, "GetOrders", 24, 36);
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名</param>
        /// <param>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(string connectionString, 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))
            {
                // 从缓存中检索存储过程参数
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);
                // 给存储过程参数分配值
                AssignParameterValues(commandParameters, parameterValues);
                return ExecuteDataset(connectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return ExecuteDataset(connectionString, CommandType.StoredProcedure, spName);
            }
        }

        /// <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>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(SqlConnection connection, CommandType commandType, string commandText)
        {
            return ExecuteDataset(connection, commandType, commandText, (SqlParameter[])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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <param>SqlParamter参数数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            // 预处理
            SqlCommand cmd = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );

            // 创建SqlDataAdapter和DataSet.
            using( SqlDataAdapter da = new SqlDataAdapter(cmd) )
            {
                DataSet ds = new DataSet();
                // 填充DataSet.
                da.Fill(ds);

                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>一个有效的数据库连接对象</param>
        /// <param>存储过程名</param>
        /// <param>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(SqlConnection 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
                SqlParameter[] commandParameters = SqlHelperParameterCache.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>事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(SqlTransaction transaction, CommandType commandType, string commandText)
        {
            return ExecuteDataset(transaction, commandType, commandText, (SqlParameter[])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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <param>SqlParamter参数数组</param>
        /// <returns>返回一个包含结果集的DataSet</returns>
        public static DataSet ExecuteDataset(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] 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
            SqlCommand cmd = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );

            // 创建 DataAdapter & DataSet
            using( SqlDataAdapter da = new SqlDataAdapter(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>事务</param>
        /// <param>存储过程名</param>
        /// <param>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(SqlTransaction 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
                SqlParameter[] commandParameters = SqlHelperParameterCache.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SqlHelper提供还是由调用者提供
        /// </summary>
        private enum SqlConnectionOwnership
        {
            /// <summary>由SqlHelper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SqlHelper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>一个有效的数据库连接对象</param>
        /// <param>一个有效的事务,或者为 ‘null‘</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <param>SqlParameters参数数组,如果没有参数则为‘null‘</param>
        /// <param>标识数据库连接对象是由调用者提供还是由SqlHelper提供</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        private static SqlDataReader ExecuteReader(SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] commandParameters, SqlConnectionOwnership connectionOwnership)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            bool mustCloseConnection = false;
            // 创建命令
            SqlCommand cmd = new SqlCommand();
            try
            {
                PrepareCommand(cmd, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );

                // 创建数据阅读器
                SqlDataReader dataReader;
                if (connectionOwnership == SqlConnectionOwnership.External)
                {
                    dataReader = cmd.ExecuteReader();
                }
                else
                {
                    dataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                }

                // 清除参数,以便再次使用..
                // HACK: There is a problem here, the output parameter values are fletched
                // when the reader is closed, so if the parameters are detached from the command
                // then the SqlReader can磘 set its values.
                // When this happen, the parameters can磘 be used again in other command.
                bool canClear = true;
                foreach(SqlParameter commandParameter in cmd.Parameters)
                {
                    if (commandParameter.Direction != ParameterDirection.Input)
                        canClear = false;
                }

                if (canClear)
                {
                    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:
        ///  SqlDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText)
        {
            return ExecuteReader(connectionString, commandType, commandText, (SqlParameter[])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:
        ///  SqlDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <param>SqlParamter参数数组(new SqlParameter("@prodid", 24))</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            SqlConnection connection = null;
            try
            {
                connection = new SqlConnection(connectionString);
                connection.Open();
                return ExecuteReader(connection, null, commandType, commandText, commandParameters,SqlConnectionOwnership.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:
        ///  SqlDataReader dr = ExecuteReader(connString, "GetOrders", 24, 36);
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名</param>
        /// <param>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SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(string connectionString, 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))
            {
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, 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:
        ///  SqlDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名或T-SQL语句</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(SqlConnection connection, CommandType commandType, string commandText)
        {
            return ExecuteReader(connection, commandType, commandText, (SqlParameter[])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:
        ///  SqlDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>SqlParamter参数数组</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
            return ExecuteReader(connection, (SqlTransaction)null, commandType, commandText, commandParameters, SqlConnectionOwnership.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:
        ///  SqlDataReader dr = ExecuteReader(conn, "GetOrders", 24, 36);
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>T存储过程名</param>
        /// <param>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SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(SqlConnection 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))
            {
                SqlParameter[] commandParameters = SqlHelperParameterCache.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:
        ///  SqlDataReader dr = ExecuteReader(trans, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(SqlTransaction transaction, CommandType commandType, string commandText)
        {
            return ExecuteReader(transaction, commandType, commandText, (SqlParameter[])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:
        ///   SqlDataReader dr = ExecuteReader(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>分配给命令的SqlParamter参数数组</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] 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, SqlConnectionOwnership.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:
        ///  SqlDataReader dr = ExecuteReader(trans, "GetOrders", 24, 36);
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>存储过程名称</param>
        /// <param>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SqlDataReader</returns>
        public static SqlDataReader ExecuteReader(SqlTransaction 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))
            {
                SqlParameter[] commandParameters = SqlHelperParameterCache.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>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(string connectionString, CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteScalar(connectionString, commandType, commandText, (SqlParameter[])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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>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(string connectionString, CommandType commandType, string commandText, params SqlParameter[] 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 (SqlConnection connection = new SqlConnection(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字符串的命令,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(connString, "GetOrderCount", 24, 36);
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名称</param>
        /// <param>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(string connectionString, 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" );

            // 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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);
                // 给存储过程参数赋值
                AssignParameterValues(commandParameters, parameterValues);
                // 调用重载方法
                return ExecuteScalar(connectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数值
                return ExecuteScalar(connectionString, CommandType.StoredProcedure, spName);
            }
        }

        /// <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>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(SqlConnection connection, CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteScalar(connection, commandType, commandText, (SqlParameter[])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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>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(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            // 创建SqlCommand命令,并进行预处理
            SqlCommand cmd = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );

            // 执行SqlCommand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>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>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(SqlConnection 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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.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>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalar(SqlTransaction transaction, CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteScalar(transaction, commandType, commandText, (SqlParameter[])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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>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(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] 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SqlCommand命令,并进行预处理
            SqlCommand cmd = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );

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

            // 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>一个有效的连接事务</param>
        /// <param>存储过程名称</param>
        /// <param>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(SqlTransaction 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 ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.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 ExecuteXmlReader XML阅读器
        /// <summary>
        /// 执行指定数据库连接对象的SqlCommand命令,并产生一个XmlReader对象做为结果集返回.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  XmlReader r = ExecuteXmlReader(conn, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句 using "FOR XML AUTO"</param>
        /// <returns>返回XmlReader结果集对象.</returns>
        public static XmlReader ExecuteXmlReader(SqlConnection connection, CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteXmlReader(connection, commandType, commandText, (SqlParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库连接对象的SqlCommand命令,并产生一个XmlReader对象做为结果集返回,指定参数.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  XmlReader r = ExecuteXmlReader(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句 using "FOR XML AUTO"</param>
        /// <param>分配给命令的SqlParamter参数数组</param>
        /// <returns>返回XmlReader结果集对象.</returns>
        public static XmlReader ExecuteXmlReader(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            bool mustCloseConnection = false;
            // 创建SqlCommand命令,并进行预处理
            SqlCommand cmd = new SqlCommand();
            try
            {
                PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection );

                // 执行命令
                XmlReader retval = cmd.ExecuteXmlReader();

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

        /// <summary>
        /// 执行指定数据库连接对象的SqlCommand命令,并产生一个XmlReader对象做为结果集返回,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:
        ///  XmlReader r = ExecuteXmlReader(conn, "GetOrders", 24, 36);
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>存储过程名称 using "FOR XML AUTO"</param>
        /// <param>分配给存储过程输入参数的对象数组</param>
        /// <returns>返回XmlReader结果集对象.</returns>
        public static XmlReader ExecuteXmlReader(SqlConnection 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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);
                // 给存储过程参数赋值
                AssignParameterValues(commandParameters, parameterValues);
                // 调用重载方法
                return ExecuteXmlReader(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数值
                return ExecuteXmlReader(connection, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// 执行指定数据库事务的SqlCommand命令,并产生一个XmlReader对象做为结果集返回.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  XmlReader r = ExecuteXmlReader(trans, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句 using "FOR XML AUTO"</param>
        /// <returns>返回XmlReader结果集对象.</returns>
        public static XmlReader ExecuteXmlReader(SqlTransaction transaction, CommandType commandType, string commandText)
        {
            // 执行参数为空的方法
            return ExecuteXmlReader(transaction, commandType, commandText, (SqlParameter[])null);
        }

        /// <summary>
        /// 执行指定数据库事务的SqlCommand命令,并产生一个XmlReader对象做为结果集返回,指定参数.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  XmlReader r = ExecuteXmlReader(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句 using "FOR XML AUTO"</param>
        /// <param>分配给命令的SqlParamter参数数组</param>
        /// <returns>返回XmlReader结果集对象.</returns>
        public static XmlReader ExecuteXmlReader(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] 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SqlCommand命令,并进行预处理
            SqlCommand cmd = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );

            // 执行命令
            XmlReader retval = cmd.ExecuteXmlReader();

            // 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SqlCommand命令,并产生一个XmlReader对象做为结果集返回,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:
        ///  XmlReader r = ExecuteXmlReader(trans, "GetOrders", 24, 36);
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>存储过程名称</param>
        /// <param>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 XmlReader ExecuteXmlReader(SqlTransaction 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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);
                // 给存储过程参数赋值
                AssignParameterValues(commandParameters, parameterValues);
                // 调用重载方法
                return ExecuteXmlReader(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // 没有参数值
                return ExecuteXmlReader(transaction, CommandType.StoredProcedure, spName);
            }
        }
        #endregion ExecuteXmlReader 阅读器结束

        #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>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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(string connectionString, 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 (SqlConnection connection = new SqlConnection(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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>分配给命令的SqlParamter参数数组</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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(string connectionString, CommandType commandType,
            string commandText, DataSet dataSet, string[] tableNames,
            params SqlParameter[] 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 (SqlConnection connection = new SqlConnection(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>一个有效的数据库连接字符串</param>
        /// <param>存储过程名称</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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>分配给存储过程输入参数的对象数组</param>
        public static void FillDataset(string connectionString, 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 (SqlConnection connection = new SqlConnection(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>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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(SqlConnection 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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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>分配给命令的SqlParamter参数数组</param>
        public static void FillDataset(SqlConnection connection, CommandType commandType,
            string commandText, DataSet dataSet, string[] tableNames,
            params SqlParameter[] 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>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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>分配给存储过程输入参数的对象数组</param>
        public static void FillDataset(SqlConnection 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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.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>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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(SqlTransaction 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 SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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>分配给命令的SqlParamter参数数组</param>
        public static void FillDataset(SqlTransaction transaction, CommandType commandType,
            string commandText, DataSet dataSet, string[] tableNames,
            params SqlParameter[] 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>一个有效的连接事务</param>
        /// <param>存储过程名称</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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>分配给存储过程输入参数的对象数组</param>
        public static void FillDataset(SqlTransaction 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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.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/SqlParameters.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  FillDataset(conn, trans, CommandType.StoredProcedure, "GetOrders", ds, new string[] {"orders"}, new SqlParameter("@prodid", 24));
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>一个有效的连接事务</param>
        /// <param>命令类型 (存储过程,命令文本或其它)</param>
        /// <param>存储过程名称或T-SQL语句</param>
        /// <param>要填充结果集的DataSet实例</param>
        /// <param>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>分配给命令的SqlParamter参数数组</param>
        private static void FillDataset(SqlConnection connection, SqlTransaction transaction, CommandType commandType,
            string commandText, DataSet dataSet, string[] tableNames,
            params SqlParameter[] commandParameters)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( dataSet == null ) throw new ArgumentNullException( "dataSet" );
            // 创建SqlCommand命令,并进行预处理
            SqlCommand command = new SqlCommand();
            bool mustCloseConnection = false;
            PrepareCommand(command, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );

            // 执行命令
            using( SqlDataAdapter dataAdapter = new SqlDataAdapter(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 UpdateDataset 更新数据集
        /// <summary>
        /// 执行数据集更新到数据库,指定inserted, updated, or deleted命令.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  UpdateDataset(conn, insertCommand, deleteCommand, updateCommand, dataSet, "Order");
        /// </remarks>
        /// <param>[追加记录]一个有效的T-SQL语句或存储过程</param>
        /// <param>[删除记录]一个有效的T-SQL语句或存储过程</param>
        /// <param>[更新记录]一个有效的T-SQL语句或存储过程</param>
        /// <param>要更新到数据库的DataSet</param>
        /// <param>要更新到数据库的DataTable</param>
        public static void UpdateDataset(SqlCommand insertCommand, SqlCommand deleteCommand, SqlCommand updateCommand, DataSet dataSet, string tableName)
        {
            if( insertCommand == null ) throw new ArgumentNullException( "insertCommand" );
            if( deleteCommand == null ) throw new ArgumentNullException( "deleteCommand" );
            if( updateCommand == null ) throw new ArgumentNullException( "updateCommand" );
            if( tableName == null || tableName.Length == 0 ) throw new ArgumentNullException( "tableName" );
            // 创建SqlDataAdapter,当操作完成后释放.
            using (SqlDataAdapter dataAdapter = new SqlDataAdapter())
            {
                // 设置数据适配器命令
                dataAdapter.UpdateCommand = updateCommand;
                dataAdapter.InsertCommand = insertCommand;
                dataAdapter.DeleteCommand = deleteCommand;
                // 更新数据集改变到数据库
                dataAdapter.Update (dataSet, tableName);
                // 提交所有改变到数据集.
                dataSet.AcceptChanges();
            }
        }
        #endregion

        #region CreateCommand 创建一条SqlCommand命令
        /// <summary>
        /// 创建SqlCommand命令,指定数据库连接对象,存储过程名和参数.
        /// </summary>
        /// <remarks>
        /// 示例:
        ///  SqlCommand command = CreateCommand(conn, "AddCustomer", "CustomerID", "CustomerName");
        /// </remarks>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>源表的列名称数组</param>
        /// <returns>返回SqlCommand命令</returns>
        public static SqlCommand CreateCommand(SqlConnection connection, string spName, params string[] sourceColumns)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            // 创建命令
            SqlCommand cmd = new SqlCommand( spName, connection );
            cmd.CommandType = CommandType.StoredProcedure;
            // 如果有参数值
            if ((sourceColumns != null) && (sourceColumns.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);
                // 将源表的列到映射到DataSet命令中.
                for (int index=0; index < sourceColumns.Length; index++)
                    commandParameters[index].SourceColumn = sourceColumns[index];
                // Attach the discovered parameters to the SqlCommand object
                AttachParameters (cmd, commandParameters);
            }
            return cmd;
        }
        #endregion

        #region ExecuteNonQueryTypedParams 类型化参数(DataRow)
        /// <summary>
        /// 执行指定连接数据库连接字符串的存储过程,使用DataRow做为参数值,返回受影响的行数.
        /// </summary>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQueryTypedParams(String connectionString, String spName, DataRow dataRow)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );

            // 如果row有值,存储过程必须初始化.
            if (dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库连接对象的存储过程,使用DataRow做为参数值,返回受影响的行数.
        /// </summary>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQueryTypedParams(SqlConnection connection, String spName, DataRow dataRow)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            // 如果row有值,存储过程必须初始化.
            if (dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库事物的存储过程,使用DataRow做为参数值,返回受影响的行数.
        /// </summary>
        /// <param>一个有效的连接事务 object</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回影响的行数</returns>
        public static int ExecuteNonQueryTypedParams(SqlTransaction transaction, String spName, DataRow dataRow)
        {
            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" );
            // Sf the row has values, the store procedure parameters must be initialized
            if (dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

                return SqlHelper.ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return SqlHelper.ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName);
            }
        }
        #endregion

        #region ExecuteDatasetTypedParams 类型化参数(DataRow)
        /// <summary>
        /// 执行指定连接数据库连接字符串的存储过程,使用DataRow做为参数值,返回DataSet.
        /// </summary>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回一个包含结果集的DataSet.</returns>
        public static DataSet ExecuteDatasetTypedParams(string connectionString, String spName, DataRow dataRow)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            //如果row有值,存储过程必须初始化.
            if ( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库连接对象的存储过程,使用DataRow做为参数值,返回DataSet.
        /// </summary>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回一个包含结果集的DataSet.</returns>
        ///
        public static DataSet ExecuteDatasetTypedParams(SqlConnection connection, String spName, DataRow dataRow)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            // 如果row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库事务的存储过程,使用DataRow做为参数值,返回DataSet.
        /// </summary>
        /// <param>一个有效的连接事务 object</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回一个包含结果集的DataSet.</returns>
        public static DataSet ExecuteDatasetTypedParams(SqlTransaction transaction, String spName, DataRow dataRow)
        {
            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row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        #region ExecuteReaderTypedParams 类型化参数(DataRow)
        /// <summary>
        /// 执行指定连接数据库连接字符串的存储过程,使用DataRow做为参数值,返回DataReader.
        /// </summary>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReaderTypedParams(String connectionString, String spName, DataRow dataRow)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );

            // 如果row有值,存储过程必须初始化.
            if ( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库连接对象的存储过程,使用DataRow做为参数值,返回DataReader.
        /// </summary>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReaderTypedParams(SqlConnection connection, String spName, DataRow dataRow)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            // 如果row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库事物的存储过程,使用DataRow做为参数值,返回DataReader.
        /// </summary>
        /// <param>一个有效的连接事务 object</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回包含结果集的SqlDataReader</returns>
        public static SqlDataReader ExecuteReaderTypedParams(SqlTransaction transaction, String spName, DataRow dataRow)
        {
            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row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

                return SqlHelper.ExecuteReader(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return SqlHelper.ExecuteReader(transaction, CommandType.StoredProcedure, spName);
            }
        }
        #endregion

        #region ExecuteScalarTypedParams 类型化参数(DataRow)
        /// <summary>
        /// 执行指定连接数据库连接字符串的存储过程,使用DataRow做为参数值,返回结果集中的第一行第一列.
        /// </summary>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalarTypedParams(String connectionString, String spName, DataRow dataRow)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );

            // 如果row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

                return SqlHelper.ExecuteScalar(connectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return SqlHelper.ExecuteScalar(connectionString, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// 执行指定连接数据库连接对象的存储过程,使用DataRow做为参数值,返回结果集中的第一行第一列.
        /// </summary>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalarTypedParams(SqlConnection connection, String spName, DataRow dataRow)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            // 如果row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库事务的存储过程,使用DataRow做为参数值,返回结果集中的第一行第一列.
        /// </summary>
        /// <param>一个有效的连接事务 object</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回结果集中的第一行第一列</returns>
        public static object ExecuteScalarTypedParams(SqlTransaction transaction, String spName, DataRow dataRow)
        {
            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row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

                return SqlHelper.ExecuteScalar(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return SqlHelper.ExecuteScalar(transaction, CommandType.StoredProcedure, spName);
            }
        }
        #endregion

        #region ExecuteXmlReaderTypedParams 类型化参数(DataRow)
        /// <summary>
        /// 执行指定连接数据库连接对象的存储过程,使用DataRow做为参数值,返回XmlReader类型的结果集.
        /// </summary>
        /// <param>一个有效的数据库连接对象</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回XmlReader结果集对象.</returns>
        public static XmlReader ExecuteXmlReaderTypedParams(SqlConnection connection, String spName, DataRow dataRow)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            // 如果row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

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

        /// <summary>
        /// 执行指定连接数据库事务的存储过程,使用DataRow做为参数值,返回XmlReader类型的结果集.
        /// </summary>
        /// <param>一个有效的连接事务 object</param>
        /// <param>存储过程名称</param>
        /// <param>使用DataRow作为参数值</param>
        /// <returns>返回XmlReader结果集对象.</returns>
        public static XmlReader ExecuteXmlReaderTypedParams(SqlTransaction transaction, String spName, DataRow dataRow)
        {
            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row有值,存储过程必须初始化.
            if( dataRow != null && dataRow.ItemArray.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. ()
                SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);

                // 分配参数值
                AssignParameterValues(commandParameters, dataRow);

                return SqlHelper.ExecuteXmlReader(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                return SqlHelper.ExecuteXmlReader(transaction, CommandType.StoredProcedure, spName);
            }
        }
        #endregion
    }

    /// <summary>
    /// SqlHelperParameterCache提供缓存存储过程参数,并能够在运行时从存储过程中探索参数.
    /// </summary>
    public sealed class SqlHelperParameterCache
    {
        #region 私有方法,字段,构造函数
        // 私有构造函数,妨止类被实例化.
        private SqlHelperParameterCache() {}
        // 这个方法要注意
        private static Hashtable paramCache = Hashtable.Synchronized(new Hashtable());
        /// <summary>
        /// 探索运行时的存储过程,返回SqlParameter参数数组.
        /// 初始化参数值为 DBNull.Value.
        /// </summary>
        /// <param>一个有效的数据库连接</param>
        /// <param>存储过程名称</param>
        /// <param>是否包含返回值参数</param>
        /// <returns>返回SqlParameter参数数组</returns>
        private static SqlParameter[] DiscoverSpParameterSet(SqlConnection connection, string spName, bool includeReturnValueParameter)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            if( spName == null || spName.Length == 0 ) throw new ArgumentNullException( "spName" );
            SqlCommand cmd = new SqlCommand(spName, connection);
            cmd.CommandType = CommandType.StoredProcedure;
            connection.Open();
            // 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.
            SqlCommandBuilder.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
            SqlParameter[] discoveredParameters = new SqlParameter[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 (SqlParameter discoveredParameter in discoveredParameters)
            {
                discoveredParameter.Value = DBNull.Value;
            }
            return discoveredParameters;
        }

        /// <summary>
        /// SqlParameter参数数组的深层拷贝.
        /// </summary>
        /// <param>原始参数数组</param>
        /// <returns>返回一个同样的参数数组</returns>
        private static SqlParameter[] CloneParameters(SqlParameter[] originalParameters)
        {
            SqlParameter[] clonedParameters = new SqlParameter[originalParameters.Length];
            for (int i = 0, j = originalParameters.Length; i < j; i++)
            {
                clonedParameters = (SqlParameter)((ICloneable)originalParameters).Clone();
            }
            return clonedParameters;
        }
        #endregion 私有方法,字段,构造函数结束

        #region 缓存方法
        /// <summary>
        /// 追加参数数组到缓存.
        /// </summary>
        /// <param>一个有效的数据库连接字符串</param>
        /// <param>存储过程名或SQL语句</param>
        /// <param>要缓存的参数数组</param>
        public static void CacheParameterSet(string connectionString, string commandText, params SqlParameter[] commandParameters)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            if( commandText == null || commandText.Length == 0 ) throw new ArgumentNullException( "commandText" );
            string hashKey = connectionString + ":" + commandText;
            paramCache[hashKey] = commandParameters;
        }

        /// <summary>
        /// 从缓存中获取参数数组.
        /// </summary>
        /// <param>一个有效的数据库连接字符</param>
        /// <param>存储过程名或SQL语句</param>
        /// <returns>参数数组</returns>
        public static SqlParameter[] GetCachedParameterSet(string connectionString, string commandText)
        {
            if( connectionString == null || connectionString.Length == 0 ) throw new ArgumentNullException( "connectionString" );
            if( commandText == null || commandText.Length == 0 ) throw new ArgumentNullException( "commandText" );
            string hashKey = connectionString + ":" + commandText;
            SqlParameter[] cachedParameters = paramCache[hashKey] as SqlParameter[];
            if (cachedParameters == null)
            {
                return null;
            }
            else
            {
                return CloneParameters(cachedParameters);
            }
        }
        #endregion 缓存方法结束

        #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>一个有效的数据库连接字符</param>
        /// <param>存储过程名</param>
        /// <returns>返回SqlParameter参数数组</returns>
        public static SqlParameter[] GetSpParameterSet(string connectionString, string spName)
        {
            return GetSpParameterSet(connectionString, 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>一个有效的数据库连接字符.</param>
        /// <param>存储过程名</param>
        /// <param>是否包含返回值参数</param>
        /// <returns>返回SqlParameter参数数组</returns>
        public static SqlParameter[] GetSpParameterSet(string connectionString, 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(SqlConnection connection = new SqlConnection(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>一个有效的数据库连接字符</param>
        /// <param>存储过程名</param>
        /// <returns>返回SqlParameter参数数组</returns>
        internal static SqlParameter[] GetSpParameterSet(SqlConnection 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>一个有效的数据库连接对象</param>
        /// <param>存储过程名</param>
        /// <param>
        /// 是否包含返回值参数
        /// </param>
        /// <returns>返回SqlParameter参数数组</returns>
        internal static SqlParameter[] GetSpParameterSet(SqlConnection connection, string spName, bool includeReturnValueParameter)
        {
            if( connection == null ) throw new ArgumentNullException( "connection" );
            using (SqlConnection clonedConnection = (SqlConnection)((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>一个有效的数据库连接对象</param>
        /// <param>存储过程名</param>
        /// <param>是否包含返回值参数</param>
        /// <returns>返回SqlParameter参数数组</returns>
        private static SqlParameter[] GetSpParameterSetInternal(SqlConnection 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":"");
            SqlParameter[] cachedParameters;

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

            return CloneParameters(cachedParameters);
        }

        #endregion 参数集检索结束
    }
}

原文地址:https://www.cnblogs.com/wenjie0904/p/10090442.html

时间: 2024-11-08 23:46:35

微软官方的SQLHelper类(含完整中文注释)(转)的相关文章

微软C#版SQLHelper.cs通用类

using System; using System.Data; using System.Xml; using System.Data.SqlClient; using System.Collections; using System.Configuration; namespace BookDAL { /// <summary> /// SqlServer数据访问帮助类 /// </summary> public sealed class SqlHelper { #region

针对勒索病毒WannaCrypt微软官方应对指南

如同其他大多数勒索软件一样,Ransom:Win32/WannaCrypt通过社会工程学尝试感染目标组织的环境,通常为带有恶意宏的Office文档附件的钓鱼邮件.一旦感染环境中的一台计算机后,该变种会尝试利用Microsoft在MS17-010补丁中修复的SMBv1的漏洞在内网中主动传播.这一蠕虫行为是真正让这一变种带来如此巨大影响的原因. https://technet.microsoft.com/zh-cn/library/security/ms17-010.aspx 微软于5月14日中午已

Win7 SP1语言包微软官方下载地址及使用方法 2

情形一:如果您的系统版本是企业版.旗舰版,可以在Windows update中检测语言包按照提示下载安装即可.如果觉得Windows update不方便的话,可以在本文第二部分中下载所需的语言包,下载完毕后双击 .exe 可执行文件就可以安装语言包. 安 装完成之后切换显示语言的方法:在开始菜单左下角的搜索框中输入“语言”作为关键字,并从搜索结果中选择“更改显示语言”,随后可以看到更改界面.在“选 择显示语言”下拉菜单中,列出了本机安装的所有语言包,从中选择要使用的语言,并单击“确定”,注销并重

.NET Framework 2.0 SP2微软官方版+.net

.net framework 2.0 Service Pack 2 是专为解决客户在 .NET Framework 2.0 发布后报告的问题而提供的累积更新.此外,此发行版为 .NET Framework 3.5 Service Pack 1 提供了性能改进和必备功能支持.请在系统需求一节中查看此部署程序包支持的操作系统.Microsoft Vista 的相应更新和 Microsoft Windows 2008 的相应更新可通过完整的 .NET Framework 3.5 service pac

微软官方常用系统工具合集

系统工具集SysinternalsSuite简介 这些小工具原本是为了解决工程师们平常在工作上遇到的各种问题而开发的,之后他们将这些工具集合起来称为 Sysinternals,并免费提供公众下载,其中部分还开源了,一直以来都颇受 IT 界人士的好评.如果把管理员比喻成战士的话,那么 Sysinternals 就是我们手中的良兵利器.熟悉和掌握这些工具,并且对 Windows 的体系有一定的了解,将大幅提高你的电脑维护.应用技能. Windows Sysinternals Suite 是一套由微软

微软官方原版win7(64位/32位)旗舰版系统下载【适合所有品牌】 此博文包含图片 转载▼

好多友友一直在问,需要微软官方win7系统,特别是64位win7旗舰版由于联想官方(其他品牌相同)没有提供(只有家庭基础版),好多都需要.网上虽然也有,但是良莠不齐,需要自己去甄别,这对于新手很困难的.基于此,我特在这里为大家提供32/64位的微软官方原版系统下载.需要注意的是,这里所提供的系统适合任何品牌的电脑,任何品牌的电脑安装之后都不能自动激活(因为不是品牌官方定制系统而是微软官方原版),需要密钥.当然这已经不是问题了,我提供的软激活也非常管用,完全和使用正版一个样!所以,如果是联想的电脑

整理出一个比较实用的SqlHelper类 满足大多数情况的使用

/// <summary> /// SqlHelper类 by zy 2017-8-17 /// </summary> public sealed class SqlHelper { //如果项目中只连接了一个数据库 那么可以在此定义一个固定的连接字符串 private static string connectionStr = ConfigurationManager.ConnectionStrings["SQLConnString1"].Connection

一大波开发者福利来了,一份微软官方Github上发布的开源项目清单等你签收

目录 微软Github开源项目入口 微软开源项目受欢迎程度排名 Visual Studio Code TypeScript RxJS .NET Core 基础类库 CNTK Microsoft calculator Monaco editor MS-DOS Redis windows版 .NET Core CLR (公共语言运行时) ASP.NET Core Entity Framework Core PowerShell 如何在其中搜索自己需要的项目 GitHub-邮件订阅 Rss订阅 最近在

Windows7下的免费虚拟机(微软官方虚拟机)

前言: 不是说windows7自带的虚拟机最好用,而是他是正式版的,免费的,仅仅要你是windows7用户,就能够免费使用: 事实上我最推荐的还是Vmware: 微软为什么提供免费的虚拟机呢? 由于vista的失败,微软认识到,假设不能为客户考虑,而单独考虑自己的技术先进性,会惹来非常多麻烦: 然而,vista和windows7的内核,都与xp有差别,有时无法兼容xp的应用: 非常多企业用户自行开发的应用或者购买的应用,是绑定在xp上的,然而微软有须要这些客户,怎么办?经过vista的失败,危机