SQLHelper.cs
//
===============================================================================
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Microsoft Data Access Application Block for .NET微软.NET数据访问程序块
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http://msdn.microsoft.com/library/en-us/dnbda/html/daab-rm.asp
(可在此网页查看)
//
//
SQLHelper.cs
//
//
This file contains the implementations of the SqlHelper and SqlHelperParameterCache
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classes. 这个文件实现了SqlHelper类和SqlHelperParameterCache类
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其中SqlHelper类执行各种方式的数据操作处理，而SqlHelperParameterCache类则是获得存储过程的参数集合
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For more information see the Data Access Application Block Implementation Overview.
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//
===============================================================================
//
Copyright (C) 2000-2001 Microsoft Corporation
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All rights reserved.
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THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY
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OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT
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LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR
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FITNESS FOR A PARTICULAR PURPOSE.
//
==============================================================================
using
System;
using
System.Data;
using
System.Xml;
using
System.Data.SqlClient;
using
System.Collections;
namespace
DataAccessTool
{
/**//// <summary>
/// The SqlHelper class is intended to encapsulate high performance, scalable best practices for /// common uses of SqlClient. /// SqlHelper类用来封装数据处理
/// </summary> public sealed class SqlHelper { private utility methods & constructors#region private utility methods & constructors public static string CONNSTR=System.Configuration.ConfigurationSettings.AppSettings["SqlServer"].ToString(); //Since this class provides only static methods, make the default constructor private to prevent //instances from being created with "new SqlHelper()". private SqlHelper() {} /**//// <summary> /// 这个方法用来将命令对象和一组参数对象联系起来 /// /// This method will assign a value of DbNull to any parameter with a direction of /// InputOutput and a value of null. 给输出类型参数对象赋空值 /// /// 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 tho be added to command</param> private static void AttachParameters(SqlCommand command, SqlParameter[] commandParameters) { foreach (SqlParameter p in commandParameters) { //check for derived output value with no value assigned if ((p.Direction == ParameterDirection.InputOutput) && (p.Value == null)) { p.Value = DBNull.Value; } command.Parameters.Add(p); } } /**//// <summary> /// 这个方法用来给一组参数对象赋值 /// </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(SqlParameter[] 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++) { 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 SqlCommand to be prepared</param> /// <param name="connection">a valid SqlConnection, on which to execute this command</param> /// <param name="transaction">a valid SqlTransaction, 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> private static void PrepareCommand(SqlCommand command, SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] commandParameters) { //if the provided connection is not open, we will open it if (connection.State != ConnectionState.Open) { connection.Open(); } //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) { 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 ExecuteNonQuery#region ExecuteNonQuery /**//// <summary> /// 执行一个指定连接串上的一个SqlCommand（不返回记录集也没有任何参数） /// Execute a SqlCommand (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 SqlConnection</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, (SqlParameter[])null); } /**//// <summary> /// 执行一个指定连接串上的一个SqlCommand（不返回记录集），使用指定的参数集 /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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 SqlParameter[] commandParameters) { //create & open a SqlConnection, and dispose of it after we are done. using (SqlConnection cn = new SqlConnection(connectionString)) { cn.Open(); //call the overload that takes a connection in place of the connection string return ExecuteNonQuery(cn, commandType, commandText, commandParameters); } } /**//// <summary> /// 执行一个存储过程并赋值，这个方法将从数据库中获得存储过程的参数对象并根据其顺序赋值 /// Execute a stored procedure via a SqlCommand (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 SqlConnection</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 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) SqlParameter[] 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); } //otherwise we can just call the SP without params else { return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns no resultset and takes no parameters) against the provided SqlConnection. /// </summary> /// <remarks> /// e.g.: /// int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders"); /// </remarks> /// <param name="connection">a valid SqlConnection</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(SqlConnection connection, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteNonQuery(connection, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns no resultset) against the specified SqlConnection /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connection">a valid SqlConnection</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(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters); //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 SqlCommand (that returns no resultset) against the specified SqlConnection /// 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 SqlConnection</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(SqlConnection connection, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection.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(connection, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns no resultset and takes no parameters) against the provided SqlTransaction. /// </summary> /// <remarks> /// e.g.: /// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders"); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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(SqlTransaction transaction, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteNonQuery(transaction, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns no resultset) against the specified SqlTransaction /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters); //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 SqlCommand (that returns no resultset) against the specified /// SqlTransaction 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 SqlTransaction</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(SqlTransaction transaction, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection.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(transaction, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName); } } #endregion ExecuteNonQuery ExecuteDataSet#region ExecuteDataSet /**//// <summary> /// Execute a SqlCommand (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 SqlConnection</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, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the database specified in the connection string /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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>a dataset containing the resultset generated by the command</returns> public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create & open a SqlConnection, and dispose of it after we are done. using (SqlConnection cn = new SqlConnection(connectionString)) { cn.Open(); //call the overload that takes a connection in place of the connection string return ExecuteDataset(cn, commandType, commandText, commandParameters); } } /**//// <summary> /// Execute a stored procedure via a SqlCommand (that returns a 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.: /// DataSet ds = ExecuteDataset(connString, "GetOrders", 24, 36); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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>a dataset containing the resultset generated by the command</returns> public static DataSet ExecuteDataset(string connectionString, string spName, params object[] parameterValues) { //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) SqlParameter[] 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 ExecuteDataset(connectionString, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteDataset(connectionString, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlConnection. /// </summary> /// <remarks> /// e.g.: /// DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders"); /// </remarks> /// <param name="connection">a valid SqlConnection</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(SqlConnection connection, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteDataset(connection, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the specified SqlConnection /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connection">a valid SqlConnection</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>a dataset containing the resultset generated by the command</returns> public static DataSet ExecuteDataset(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters); //create the DataAdapter & DataSet SqlDataAdapter da = new SqlDataAdapter(cmd); DataSet ds = new DataSet(); //fill the DataSet using default values for DataTable names, etc. da.Fill(ds); // detach the SqlParameters from the command object, so they can be used again. cmd.Parameters.Clear(); //return the dataset return ds; } /**//// <summary> /// Execute a stored procedure via a SqlCommand (that returns a resultset) against the specified SqlConnection /// 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.: /// DataSet ds = ExecuteDataset(conn, "GetOrders", 24, 36); /// </remarks> /// <param name="connection">a valid SqlConnection</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>a dataset containing the resultset generated by the command</returns> public static DataSet ExecuteDataset(SqlConnection connection, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection.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 ExecuteDataset(connection, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteDataset(connection, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlTransaction. /// </summary> /// <remarks> /// e.g.: /// DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders"); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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(SqlTransaction transaction, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteDataset(transaction, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the specified SqlTransaction /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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>a dataset containing the resultset generated by the command</returns> public static DataSet ExecuteDataset(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters); //create the DataAdapter & DataSet SqlDataAdapter da = new SqlDataAdapter(cmd); DataSet ds = new DataSet(); //fill the DataSet using default values for DataTable names, etc. da.Fill(ds); // detach the SqlParameters from the command object, so they can be used again. cmd.Parameters.Clear(); //return the dataset return ds; } /**//// <summary> /// Execute a stored procedure via a SqlCommand (that returns a resultset) against the specified /// SqlTransaction 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.: /// DataSet ds = ExecuteDataset(trans, "GetOrders", 24, 36); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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>a dataset containing the resultset generated by the command</returns> public static DataSet ExecuteDataset(SqlTransaction transaction, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection.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 ExecuteDataset(transaction, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteDataset(transaction, CommandType.StoredProcedure, spName); } } #endregion ExecuteDataSet ExecuteReader#region ExecuteReader /**//// <summary> /// this enum is used to indicate whether the connection was provided by the caller, or created by SqlHelper, so that /// we can set the appropriate CommandBehavior when calling ExecuteReader() /// </summary> private enum SqlConnectionOwnership { /**//// <summary>Connection is owned and managed by SqlHelper</summary> Internal, /**//// <summary>Connection is owned and managed by the caller</summary> External } /**//// <summary> /// Create and prepare a SqlCommand, and call ExecuteReader with the appropriate CommandBehavior. /// </summary> /// <remarks> /// If we created and opened the connection, we want the connection to be closed when the DataReader is closed. /// /// If the caller provided the connection, we want to leave it to them to manage. /// </remarks> /// <param name="connection">a valid SqlConnection, on which to execute this command</param> /// <param name="transaction">a valid SqlTransaction, 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="connectionOwnership">indicates whether the connection parameter was provided by the caller, or created by SqlHelper</param> /// <returns>SqlDataReader containing the results of the command</returns> private static SqlDataReader ExecuteReader(SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] commandParameters, SqlConnectionOwnership connectionOwnership) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, transaction, commandType, commandText, commandParameters); //create a reader SqlDataReader dr; // call ExecuteReader with the appropriate CommandBehavior if (connectionOwnership == SqlConnectionOwnership.External) { dr = cmd.ExecuteReader(); } else { dr = cmd.ExecuteReader(CommandBehavior.CloseConnection); } // detach the SqlParameters from the command object, so they can be used again. cmd.Parameters.Clear(); return dr; } /**//// <summary> /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the database specified in /// the connection string. /// </summary> /// <remarks> /// e.g.: /// SqlDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders"); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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 SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteReader(connectionString, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the database specified in the connection string /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// SqlDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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>a SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create & open a SqlConnection SqlConnection cn = new SqlConnection(connectionString); cn.Open(); try { //call the private overload that takes an internally owned connection in place of the connection string return ExecuteReader(cn, null, commandType, commandText, commandParameters,SqlConnectionOwnership.Internal); } catch { //if we fail to return the SqlDatReader, we need to close the connection ourselves cn.Close(); throw; } } /**//// <summary> /// Execute a stored procedure via a SqlCommand (that returns a 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.: /// SqlDataReader dr = ExecuteReader(connString, "GetOrders", 24, 36); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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>a SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(string connectionString, string spName, params object[] parameterValues) { //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) SqlParameter[] 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 ExecuteReader(connectionString, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteReader(connectionString, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlConnection. /// </summary> /// <remarks> /// e.g.: /// SqlDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders"); /// </remarks> /// <param name="connection">a valid SqlConnection</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 SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(SqlConnection connection, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteReader(connection, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the specified SqlConnection /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// SqlDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connection">a valid SqlConnection</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>a SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //pass through the call to the private overload using a null transaction value and an externally owned connection return ExecuteReader(connection, (SqlTransaction)null, commandType, commandText, commandParameters, SqlConnectionOwnership.External); } /**//// <summary> /// Execute a stored procedure via a SqlCommand (that returns a resultset) against the specified SqlConnection /// 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.: /// SqlDataReader dr = ExecuteReader(conn, "GetOrders", 24, 36); /// </remarks> /// <param name="connection">a valid SqlConnection</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>a SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(SqlConnection connection, string spName, params object[] parameterValues) { //if we receive parameter values, we need to figure out where they go if ((parameterValues != null) && (parameterValues.Length > 0)) { SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection.ConnectionString, spName); AssignParameterValues(commandParameters, parameterValues); return ExecuteReader(connection, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteReader(connection, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlTransaction. /// </summary> /// <remarks> /// e.g.: /// SqlDataReader dr = ExecuteReader(trans, CommandType.StoredProcedure, "GetOrders"); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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 SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(SqlTransaction transaction, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteReader(transaction, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the specified SqlTransaction /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// SqlDataReader dr = ExecuteReader(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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>a SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //pass through to private overload, indicating that the connection is owned by the caller return ExecuteReader(transaction.Connection, transaction, commandType, commandText, commandParameters, SqlConnectionOwnership.External); } /**//// <summary> /// Execute a stored procedure via a SqlCommand (that returns a resultset) against the specified /// SqlTransaction 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.: /// SqlDataReader dr = ExecuteReader(trans, "GetOrders", 24, 36); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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>a SqlDataReader containing the resultset generated by the command</returns> public static SqlDataReader ExecuteReader(SqlTransaction transaction, string spName, params object[] parameterValues) { //if we receive parameter values, we need to figure out where they go if ((parameterValues != null) && (parameterValues.Length > 0)) { SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection.ConnectionString, spName); AssignParameterValues(commandParameters, parameterValues); return ExecuteReader(transaction, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteReader(transaction, CommandType.StoredProcedure, spName); } } #endregion ExecuteReader ExecuteScalar#region ExecuteScalar /**//// <summary> /// Execute a SqlCommand (that returns a 1x1 resultset and takes no parameters) against the database specified in /// the connection string. /// </summary> /// <remarks> /// e.g.: /// int orderCount = (int)ExecuteScalar(connString, CommandType.StoredProcedure, "GetOrderCount"); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(string connectionString, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteScalar(connectionString, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a 1x1 resultset) against the database specified in the connection string /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// int orderCount = (int)ExecuteScalar(connString, CommandType.StoredProcedure, "GetOrderCount", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create & open a SqlConnection, and dispose of it after we are done. using (SqlConnection cn = new SqlConnection(connectionString)) { cn.Open(); //call the overload that takes a connection in place of the connection string return ExecuteScalar(cn, commandType, commandText, commandParameters); } } /**//// <summary> /// Execute a stored procedure via a SqlCommand (that returns a 1x1 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 orderCount = (int)ExecuteScalar(connString, "GetOrderCount", 24, 36); /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(string connectionString, string spName, params object[] parameterValues) { //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) SqlParameter[] 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 ExecuteScalar(connectionString, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteScalar(connectionString, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns a 1x1 resultset and takes no parameters) against the provided SqlConnection. /// </summary> /// <remarks> /// e.g.: /// int orderCount = (int)ExecuteScalar(conn, CommandType.StoredProcedure, "GetOrderCount"); /// </remarks> /// <param name="connection">a valid SqlConnection</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(SqlConnection connection, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteScalar(connection, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a 1x1 resultset) against the specified SqlConnection /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// int orderCount = (int)ExecuteScalar(conn, CommandType.StoredProcedure, "GetOrderCount", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connection">a valid SqlConnection</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters); //execute the command & return the results object retval = cmd.ExecuteScalar(); // 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 SqlCommand (that returns a 1x1 resultset) against the specified SqlConnection /// 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 orderCount = (int)ExecuteScalar(conn, "GetOrderCount", 24, 36); /// </remarks> /// <param name="connection">a valid SqlConnection</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(SqlConnection connection, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection.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 ExecuteScalar(connection, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteScalar(connection, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns a 1x1 resultset and takes no parameters) against the provided SqlTransaction. /// </summary> /// <remarks> /// e.g.: /// int orderCount = (int)ExecuteScalar(trans, CommandType.StoredProcedure, "GetOrderCount"); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(SqlTransaction transaction, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteScalar(transaction, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a 1x1 resultset) against the specified SqlTransaction /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// int orderCount = (int)ExecuteScalar(trans, CommandType.StoredProcedure, "GetOrderCount", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters); //execute the command & return the results object retval = cmd.ExecuteScalar(); // 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 SqlCommand (that returns a 1x1 resultset) against the specified /// SqlTransaction 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 orderCount = (int)ExecuteScalar(trans, "GetOrderCount", 24, 36); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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 object containing the value in the 1x1 resultset generated by the command</returns> public static object ExecuteScalar(SqlTransaction transaction, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection.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 ExecuteScalar(transaction, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteScalar(transaction, CommandType.StoredProcedure, spName); } } #endregion ExecuteScalar ExecuteXmlReader#region ExecuteXmlReader /**//// <summary> /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlConnection. /// </summary> /// <remarks> /// e.g.: /// XmlReader r = ExecuteXmlReader(conn, CommandType.StoredProcedure, "GetOrders"); /// </remarks> /// <param name="connection">a valid SqlConnection</param> /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param> /// <param name="commandText">the stored procedure name or T-SQL command using "FOR XML AUTO"</param> /// <returns>an XmlReader containing the resultset generated by the command</returns> public static XmlReader ExecuteXmlReader(SqlConnection connection, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteXmlReader(connection, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the specified SqlConnection /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// XmlReader r = ExecuteXmlReader(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="connection">a valid SqlConnection</param> /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param> /// <param name="commandText">the stored procedure name or T-SQL command using "FOR XML AUTO"</param> /// <param name="commandParameters">an array of SqlParamters used to execute the command</param> /// <returns>an XmlReader containing the resultset generated by the command</returns> public static XmlReader ExecuteXmlReader(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters); //create the DataAdapter & DataSet XmlReader retval = cmd.ExecuteXmlReader(); // 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 SqlCommand (that returns a resultset) against the specified SqlConnection /// 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.: /// XmlReader r = ExecuteXmlReader(conn, "GetOrders", 24, 36); /// </remarks> /// <param name="connection">a valid SqlConnection</param> /// <param name="spName">the name of the stored procedure using "FOR XML AUTO"</param> /// <param name="parameterValues">an array of objects to be assigned as the input values of the stored procedure</param> /// <returns>an XmlReader containing the resultset generated by the command</returns> public static XmlReader ExecuteXmlReader(SqlConnection connection, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(connection.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 ExecuteXmlReader(connection, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteXmlReader(connection, CommandType.StoredProcedure, spName); } } /**//// <summary> /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlTransaction. /// </summary> /// <remarks> /// e.g.: /// XmlReader r = ExecuteXmlReader(trans, CommandType.StoredProcedure, "GetOrders"); /// </remarks> /// <param name="transaction">a valid SqlTransaction</param> /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param> /// <param name="commandText">the stored procedure name or T-SQL command using "FOR XML AUTO"</param> /// <returns>an XmlReader containing the resultset generated by the command</returns> public static XmlReader ExecuteXmlReader(SqlTransaction transaction, CommandType commandType, string commandText) { //pass through the call providing null for the set of SqlParameters return ExecuteXmlReader(transaction, commandType, commandText, (SqlParameter[])null); } /**//// <summary> /// Execute a SqlCommand (that returns a resultset) against the specified SqlTransaction /// using the provided parameters. /// </summary> /// <remarks> /// e.g.: /// XmlReader r = ExecuteXmlReader(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24)); /// </remarks> /// <param name="transaction">a valid SqlTransaction</param> /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param> /// <param name="commandText">the stored procedure name or T-SQL command using "FOR XML AUTO"</param> /// <param name="commandParameters">an array of SqlParamters used to execute the command</param> /// <returns>an XmlReader containing the resultset generated by the command</returns> public static XmlReader ExecuteXmlReader(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters) { //create a command and prepare it for execution SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters); //create the DataAdapter & DataSet XmlReader retval = cmd.ExecuteXmlReader(); // 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 SqlCommand (that returns a resultset) against the specified /// SqlTransaction 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.: /// XmlReader r = ExecuteXmlReader(trans, "GetOrders", 24, 36); /// </remarks> /// <param name="transaction">a valid SqlTransaction</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>a dataset containing the resultset generated by the command</returns> public static XmlReader ExecuteXmlReader(SqlTransaction transaction, string spName, params object[] parameterValues) { //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) SqlParameter[] commandParameters = SqlHelperParameterCache.GetSpParameterSet(transaction.Connection.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 ExecuteXmlReader(transaction, CommandType.StoredProcedure, spName, commandParameters); } //otherwise we can just call the SP without params else { return ExecuteXmlReader(transaction, CommandType.StoredProcedure, spName); } } #endregion ExecuteXmlReader } /**//// <summary> /// SqlHelperParameterCache provides functions to leverage a static cache of procedure parameters, and the /// ability to discover parameters for stored procedures at run-time. /// SqlHelperParameterCache支持函数来实现静态缓存存储过程参数，并支持在运行时得到存储过程的参数 /// </summary> public sealed class SqlHelperParameterCache { private methods, variables, and constructors#region private methods, variables, and constructors //Since this class provides only static methods, make the default constructor private to prevent //instances from being created with "new SqlHelperParameterCache()". //类提供的都是静态方法，将默认构造函数设置为私有的以便阻止利用"new SqlHelperParameterCache()"来实例化类 private SqlHelperParameterCache() {} //存储过程参数缓存导HashTable中 private static Hashtable paramCache = Hashtable.Synchronized(new Hashtable()); /**//// <summary> /// resolve at run time the appropriate set of SqlParameters for a stored procedure /// 在运行时得到一个存储过程的一系列参数信息 /// </summary> /// <param name="connectionString">a valid connection string for a SqlConnection</param> /// <param name="connectionString">一个连接对象的有效连接串</param> /// <param name="spName">the name of the stored procedure</param> /// <param name="spName">存储过程名</param> /// <param name="includeReturnValueParameter">是否有返回值参数</param> /// <returns>参数对象数组，存储过程的所有参数信息</returns> private static SqlParameter[] DiscoverSpParameterSet(string connectionString, string spName, bool includeReturnValueParameter) { using (SqlConnection cn = new SqlConnection(connectionString)) using (SqlCommand cmd = new SqlCommand(spName,cn)) { cn.Open(); cmd.CommandType = CommandType.StoredProcedure; //从 SqlCommand 指定的存储过程中检索参数信息，并填充指定的 SqlCommand 对象的 Parameters 集。 SqlCommandBuilder.DeriveParameters(cmd); if (!includeReturnValueParameter) { //移除第一个参数对象，因为没有返回值，而默认情况下，第一个参数对象是返回值 cmd.Parameters.RemoveAt(0); } SqlParameter[] discoveredParameters = new SqlParameter[cmd.Parameters.Count];; cmd.Parameters.CopyTo(discoveredParameters, 0); return discoveredParameters; } } //deep copy of cached SqlParameter array //复制缓存参数数组（克隆） private static SqlParameter[] CloneParameters(SqlParameter[] originalParameters) { SqlParameter[] clonedParameters = new SqlParameter[originalParameters.Length]; for (int i = 0, j = originalParameters.Length; i < j; i++) { clonedParameters[i] = (SqlParameter)((ICloneable)originalParameters[i]).Clone(); } return clonedParameters; } #endregion private methods, variables, and constructors caching functions#region caching functions /**//// <summary> /// 将参数数组添加到缓存中 /// </summary> /// <param name="connectionString">有效的连接串</param> /// <param name="commandText">一个存储过程名或者T-SQL命令</param> /// <param name="commandParameters">一个要被缓存的参数对象数组</param> public static void CacheParameterSet(string connectionString, string commandText, params SqlParameter[] commandParameters) { string hashKey = connectionString + ":" + commandText; paramCache[hashKey] = commandParameters; } /**//// <summary> /// 从缓存中获得参数对象数组 /// </summary> /// <param name="connectionString">有效的连接串</param> /// <param name="commandText">一个存储过程名或者T-SQL命令</param> /// <returns>一个参数对象数组</returns> public static SqlParameter[] GetCachedParameterSet(string connectionString, string commandText) { string hashKey = connectionString + ":" + commandText; SqlParameter[] cachedParameters = (SqlParameter[])paramCache[hashKey]; if (cachedParameters == null) { return null; } else { return CloneParameters(cachedParameters); } } #endregion caching functions Parameter Discovery Functions#region Parameter Discovery Functions /**//// <summary> /// 获得存储过程的参数集 /// </summary> /// <remarks> /// 这个方法从数据库中获得信息，并将之存储在缓存，以便之后的使用 /// </remarks> /// <param name="connectionString">有效的连接串</param> /// <param name="commandText">一个存储过程名或者T-SQL命令</param> /// <returns>一个参数对象数组</returns> public static SqlParameter[] GetSpParameterSet(string connectionString, string spName) { return GetSpParameterSet(connectionString, spName, false); } /**//// <summary> /// 获得存储过程的参数集 /// </summary> /// <remarks> /// 这个方法从数据库中获得信息，并将之存储在缓存，以便之后的使用 /// </remarks> /// <param name="connectionString">a valid connection string for a SqlConnection</param> /// <param name="spName">the name of the stored procedure</param> /// <param name="includeReturnValueParameter">a bool value indicating whether the return value parameter should be included in the results</param> /// <returns>an array of SqlParameters</returns> /// <param name="connectionString">有效的连接串</param> /// <param name="commandText">一个存储过程名</param> /// /// <param name="includeReturnValueParameter">是否有返回值参数</param> /// <returns>一个参数对象数组</returns> public static SqlParameter[] GetSpParameterSet(string connectionString, string spName, bool includeReturnValueParameter) { string hashKey = connectionString + ":" + spName + (includeReturnValueParameter ? ":include ReturnValue Parameter":""); SqlParameter[] cachedParameters; cachedParameters = (SqlParameter[])paramCache[hashKey]; if (cachedParameters == null) { cachedParameters = (SqlParameter[])(paramCache[hashKey] = DiscoverSpParameterSet(connectionString, spName, includeReturnValueParameter)); } return CloneParameters(cachedParameters); } #endregion Parameter Discovery Functions }
}