参考SQLHelper编写的OracleHelper

// ===============================================================================
// Microsoft Data Access Application Block for .NET
// http://msdn.microsoft.com/library/en-us/dnbda/html/daab-rm.asp
//
// EfOracleHelper.cs
//
// This file contains the implementations of the EfOracleHelper and SqlHelperParameterCache
// classes.
//
// For more information see the Data Access Application Block Implementation Overview. 
// ===============================================================================
// Release history
// VERSION    DESCRIPTION
//   2.0    Added support for FillDataset, UpdateDataset and "Param" helper methods
//
// ===============================================================================
// Copyright (C) 2000-2001 Microsoft Corporation
// All rights reserved.
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY
// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT
// LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR
// FITNESS FOR A PARTICULAR PURPOSE.
// ==============================================================================

using System;
using System.Configuration;
using System.Data;
using Oracle.ManagedDataAccess.Client;
using System.Collections;
using System.Text;
using System.Collections.Generic;
using System.Linq;
using System.Xml;

namespace Oracle
{
    /// <summary>
    /// The EfOracleHelper class is intended to encapsulate high performance, scalable best practices for 
    /// common uses of SqlClient
    /// </summary>
    public sealed class OracleHelper
    {
        #region private utility methods & constructors

        // Since this class provides only static methods, make the default constructor private to prevent 
        // instances from being created with "new EfOracleHelper()"
        private OracleHelper() { }
/// <summary>
        /// This method is used to attach array of SqlParameters to a OracleCommand.
        /// 
        /// This method will assign a value of DbNull to any parameter with a direction of
        /// InputOutput and a value of null.  
        /// 
        /// This behavior will prevent default values from being used, but
        /// this will be the less common case than an intended pure output parameter (derived as InputOutput)
        /// where the user provided no input value.
        /// </summary>
        /// <param name="command">The command to which the parameters will be added</param>
        /// <param name="commandParameters">An array of SqlParameters to be added to command</param>
        private static void AttachParameters(OracleCommand command, OracleParameter[] commandParameters)
        {
            if (command == null) throw new ArgumentNullException("command");
            if (commandParameters != null)
            {
                foreach (OracleParameter p in commandParameters)
                {
                    if (p != null)
                    {
                        // Check for derived output value with no value assigned
                        if ((p.Direction == ParameterDirection.InputOutput ||
                            p.Direction == ParameterDirection.Input) &&
                            (p.Value == null))
                        {
                            p.Value = DBNull.Value;
                        }
                        command.Parameters.Add(p);
                    }
                }
            }
        }

        /// <summary>
        /// This method assigns dataRow column values to an array of SqlParameters
        /// </summary>
        /// <param name="commandParameters">Array of SqlParameters to be assigned values</param>
        /// <param name="dataRow">The dataRow used to hold the stored procedure‘s parameter values</param>
        private static void AssignParameterValues(OracleParameter[] commandParameters, DataRow dataRow)
        {
            if ((commandParameters == null) || (dataRow == null))
            {
                // Do nothing if we get no data
                return;
            }

            int i = 0;
            // Set the parameters values
            foreach (OracleParameter commandParameter in commandParameters)
            {
                // Check the parameter name
                if (commandParameter.ParameterName == null ||
                    commandParameter.ParameterName.Length <= 1)
                    throw new Exception(
                        string.Format(
                            "Please provide a valid parameter name on the parameter #{0}, the ParameterName property has the following value: ‘{1}‘.",
                            i, commandParameter.ParameterName));
                if (dataRow.Table.Columns.IndexOf(commandParameter.ParameterName.Substring(1)) != -1)
                    commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
                i++;
            }
        }

        /// <summary>
        /// This method assigns an array of values to an array of SqlParameters
        /// </summary>
        /// <param name="commandParameters">Array of SqlParameters to be assigned values</param>
        /// <param name="parameterValues">Array of objects holding the values to be assigned</param>
        private static void AssignParameterValues(OracleParameter[] commandParameters, object[] parameterValues)
        {
            if ((commandParameters == null) || (parameterValues == null))
            {
                // Do nothing if we get no data
                return;
            }

            // We must have the same number of values as we pave parameters to put them in
            if (commandParameters.Length != parameterValues.Length)
            {
                throw new ArgumentException("Parameter count does not match Parameter Value count.");
            }

            // Iterate through the SqlParameters, assigning the values from the corresponding position in the 
            // value array
            for (int i = 0, j = commandParameters.Length; i < j; i++)
            {
                // If the current array value derives from IDbDataParameter, then assign its Value property
                if (parameterValues[i] is IDbDataParameter)
                {
                    IDbDataParameter paramInstance = (IDbDataParameter)parameterValues[i];
                    if (paramInstance.Value == null)
                    {
                        commandParameters[i].Value = DBNull.Value;
                    }
                    else
                    {
                        commandParameters[i].Value = paramInstance.Value;
                    }
                }
                else if (parameterValues[i] == null)
                {
                    commandParameters[i].Value = DBNull.Value;
                }
                else
                {
                    commandParameters[i].Value = parameterValues[i];
                }
            }
        }

        /// <summary>
        /// This method opens (if necessary) and assigns a connection, transaction, command type and parameters 
        /// to the provided command
        /// </summary>
        /// <param name="command">The OracleCommand to be prepared</param>
        /// <param name="connection">A valid OracleConnection, on which to execute this command</param>
        /// <param name="transaction">A valid OracleTransaction, or ‘null‘</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <param name="commandParameters">An array of SqlParameters to be associated with the command or ‘null‘ if no parameters are required</param>
        /// <param name="mustCloseConnection"><c>true</c> if the connection was opened by the method, otherwose is false.</param>
        private static void PrepareCommand(OracleCommand command, OracleConnection connection, OracleTransaction transaction, CommandType commandType, string commandText, OracleParameter[] 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;
            }

            // Associate the connection with the command
            command.Connection = connection;

            // Set the command text (stored procedure name or SQL statement)
            command.CommandText = commandText;

            // If we were provided a transaction, assign it
            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;
            }

            // Set the command type
            command.CommandType = commandType;

            // Attach the command parameters if they are provided
            if (commandParameters != null)
            {
                AttachParameters(command, commandParameters);
            }
            return;
        }

        #endregion private utility methods & constructors

        #region ExecuteNonQuery

        /// <summary>
        /// Execute a OracleCommand (that returns no resultset and takes no parameters) against the database specified in 
        /// the connection string
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="connectionString">A valid connection string for a OracleConnection</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteNonQuery(connectionString, commandType, commandText, (OracleParameter[])null);
        }

        /// <summary>
        /// Execute a OracleCommand (that returns no resultset) against the database specified in the connection string 
        /// using the provided parameters
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new OracleParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connectionString">A valid connection string for a OracleConnection</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <param name="commandParameters">An array of SqlParamters used to execute the command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText, params OracleParameter[] commandParameters)
        {
            if (connectionString == null || connectionString.Length == 0) throw new ArgumentNullException("connectionString");

            // Create & open a OracleConnection, and dispose of it after we are done
            using (OracleConnection connection = new OracleConnection(connectionString))
            {
                connection.Open();

                // Call the overload that takes a connection in place of the connection string
                return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
            }
        }

        /// <summary>
        /// Execute a stored procedure via a OracleCommand (that returns no resultset) against the database specified in 
        /// the connection string using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure‘s return value parameter.
        /// 
        /// e.g.:  
        ///  int result = ExecuteNonQuery(connString, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="connectionString">A valid connection string for a OracleConnection</param>
        /// <param name="spName">The name of the stored prcedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>An int representing the number of rows affected by the command</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");

            // If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                OracleParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);

                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);

                // Call the overload that takes an array of SqlParameters
                return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // Otherwise we can just call the SP without params
                return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// Execute a OracleCommand (that returns no resultset and takes no parameters) against the provided OracleConnection. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="connection">A valid OracleConnection</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleConnection connection, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteNonQuery(connection, commandType, commandText, (OracleParameter[])null);
        }

        /// <summary>
        /// Execute a OracleCommand (that returns no resultset) against the specified OracleConnection 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new OracleParameter("@prodid", 24));
        /// </remarks>
        /// <param name="connection">A valid OracleConnection</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <param name="commandParameters">An array of SqlParamters used to execute the command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleConnection connection, CommandType commandType, string commandText, params OracleParameter[] commandParameters)
        {
            if (connection == null) throw new ArgumentNullException("connection");

            // Create a command and prepare it for execution
            OracleCommand cmd = new OracleCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, connection, (OracleTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);

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

            // Detach the SqlParameters from the command object, so they can be used again
            cmd.Parameters.Clear();
            if (mustCloseConnection)
                connection.Close();
            return retval;
        }

        /// <summary>
        /// Execute a stored procedure via a OracleCommand (that returns no resultset) against the specified OracleConnection 
        /// using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure‘s return value parameter.
        /// 
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="connection">A valid OracleConnection</param>
        /// <param name="spName">The name of the stored procedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleConnection connection, string spName, params object[] parameterValues)
        {
            if (connection == null) throw new ArgumentNullException("connection");
            if (spName == null || spName.Length == 0) throw new ArgumentNullException("spName");

            // If we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                OracleParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection, spName);

                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);

                // Call the overload that takes an array of SqlParameters
                return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // Otherwise we can just call the SP without params
                return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName);
            }
        }

        /// <summary>
        /// Execute a OracleCommand (that returns no resultset and takes no parameters) against the provided OracleTransaction. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders");
        /// </remarks>
        /// <param name="transaction">A valid OracleTransaction</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleTransaction transaction, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteNonQuery(transaction, commandType, commandText, (OracleParameter[])null);
        }

        /// <summary>
        /// Execute a OracleCommand (that returns no resultset) against the specified OracleTransaction
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new OracleParameter("@prodid", 24));
        /// </remarks>
        /// <param name="transaction">A valid OracleTransaction</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <param name="commandParameters">An array of SqlParamters used to execute the command</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleTransaction transaction, CommandType commandType, string commandText, params OracleParameter[] 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");

            // Create a command and prepare it for execution
            OracleCommand cmd = new OracleCommand();
            bool mustCloseConnection = false;
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);

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

            // Detach the SqlParameters from the command object, so they can be used again
            cmd.Parameters.Clear();
            return retval;
        }

        /// <summary>
        /// Execute a stored procedure via a OracleCommand (that returns no resultset) against the specified 
        /// OracleTransaction using the provided parameter values.  This method will query the database to discover the parameters for the 
        /// stored procedure (the first time each stored procedure is called), and assign the values based on parameter order.
        /// </summary>
        /// <remarks>
        /// This method provides no access to output parameters or the stored procedure‘s return value parameter.
        /// 
        /// e.g.:  
        ///  int result = ExecuteNonQuery(conn, trans, "PublishOrders", 24, 36);
        /// </remarks>
        /// <param name="transaction">A valid OracleTransaction</param>
        /// <param name="spName">The name of the stored procedure</param>
        /// <param name="parameterValues">An array of objects to be assigned as the input values of the stored procedure</param>
        /// <returns>An int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleTransaction 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 we receive parameter values, we need to figure out where they go
            if ((parameterValues != null) && (parameterValues.Length > 0))
            {
                // Pull the parameters for this stored procedure from the parameter cache (or discover them & populate the cache)
                OracleParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);

                // Assign the provided values to these parameters based on parameter order
                AssignParameterValues(commandParameters, parameterValues);

                // Call the overload that takes an array of SqlParameters
                return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName, commandParameters);
            }
            else
            {
                // Otherwise we can just call the SP without params
                return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName);
            }
        }

        #endregion ExecuteNonQuery

        #region ExecuteDataset

        /// <summary>
        /// Execute a OracleCommand (that returns a resultset and takes no parameters) against the database specified in 
        /// the connection string. 
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders");
        /// </remarks>
        /// <param name="connectionString">A valid connection string for a OracleConnection</param>
        /// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">The stored procedure name or T-SQL command</param>
        /// <returns>A dataset containing the resultset generated by the command</returns>
        public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText)
        {
            // Pass through the call providing null for the set of SqlParameters
            return ExecuteDataset(connectionString, commandType, commandText, (OracleParameter[])null);
        }

        /// <summary>
        /// Execute a OracleCommand (that returns a resultset) against the database specified in the connection string 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>