System;
using System.Data;
using System.Xml;
using System.Data.SqlClient;
using System.Collections;
using System.Configuration;
namespace BookDAL
{
/// <summary>
/// SqlServer数据访问帮助类
/// </summary>
public sealed class SqlHelper
{
#region 私有构造函数和方法
private SqlHelper() { }
/// <summary>
/// 将SqlParameter参数数组(参数值)分配给SqlCommand命令.
/// 这个方法将给任何一个参数分配DBNull.Value;
/// 该操作将阻止默认值的使用.
/// </summary>
/// <param name="command">命令名</param>
/// <param name="commandParameters">SqlParameters数组</param>
private static void AttachParameters(SqlCommand command, SqlParameter[] commandParameters)
{
if (command ==
null)
throw new ArgumentNullException(
"command");
if (commandParameters !=
null)
{
foreach (SqlParameter p
in commandParameters)
{
if (p !=
null)
{
// 检查未分配值的输出参数,将其分配以DBNull.Value.
if ((p.Direction == ParameterDirection.InputOutput || p.Direction == ParameterDirection.Input) &&
(p.Value ==
null))
{
p.Value =
DBNull.Value;
}
command.Parameters.Add(p);
}
}
}
}
/// <summary>
/// 将DataRow类型的列值分配到SqlParameter参数数组.
/// </summary>
/// <param name="commandParameters">要分配值的SqlParameter参数数组</param>
/// <param name="dataRow">将要分配给存储过程参数的DataRow</param>
private static void AssignParameterValues(SqlParameter[] commandParameters, DataRow dataRow)
{
if ((commandParameters ==
null) || (dataRow ==
null))
{
return;
}
int i =
0;
// 设置参数值
foreach (SqlParameter commandParameter
in commandParameters)
{
// 创建参数名称,如果不存在,只抛出一个异常.
if (commandParameter.ParameterName ==
null ||
commandParameter.ParameterName.Length <=
1)
throw new Exception(
string.Format(
"请提供参数{0}一个有效的名称{1}.", i, commandParameter.ParameterName));
// 从dataRow的表中获取为参数数组中数组名称的列的索引.
// 如果存在和参数名称相同的列,则将列值赋给当前名称的参数.
if (dataRow.Table.Columns.IndexOf(commandParameter.ParameterName.Substring(
1)) != -
1)
commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(
1)];
i++
;
}
}
/// <summary>
/// 将一个对象数组分配给SqlParameter参数数组.
/// </summary>
/// <param name="commandParameters">要分配值的SqlParameter参数数组</param>
/// <param name="parameterValues">将要分配给存储过程参数的对象数组</param>
private static void AssignParameterValues(SqlParameter[] commandParameters,
object[] parameterValues)
{
if ((commandParameters ==
null) || (parameterValues ==
null))
{
return;
}
// 确保对象数组个数与参数个数匹配,如果不匹配,抛出一个异常.
if (commandParameters.Length !=
parameterValues.Length)
{
throw new ArgumentException(
"参数值个数与参数不匹配.");
}
// 给参数赋值
for (
int i =
0, j = commandParameters.Length; i < j; i++
)
{
// If the current array value derives from IDbDataParameter, then assign its Value property
if (parameterValues[i]
is IDbDataParameter)
{
IDbDataParameter paramInstance =
(IDbDataParameter)parameterValues[i];
if (paramInstance.Value ==
null)
{
commandParameters[i].Value =
DBNull.Value;
}
else
{
commandParameters[i].Value =
paramInstance.Value;
}
}
else if (parameterValues[i] ==
null)
{
commandParameters[i].Value =
DBNull.Value;
}
else
{
commandParameters[i].Value =
parameterValues[i];
}
}
}
/// <summary>
/// 预处理用户提供的命令,数据库连接/事务/命令类型/参数
/// </summary>
/// <param name="command">要处理的SqlCommand</param>
/// <param name="connection">数据库连接</param>
/// <param name="transaction">一个有效的事务或者是null值</param>
/// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
/// <param name="commandText">存储过程名或都T-SQL命令文本</param>
/// <param name="commandParameters">和命令相关联的SqlParameter参数数组,如果没有参数为‘null‘</param>
/// <param name="mustCloseConnection"><c>true</c> 如果连接是打开的,则为true,其它情况下为false.</param>
private static void PrepareCommand(SqlCommand command, SqlConnection connection, SqlTransaction transaction, CommandType commandType,
string commandText, SqlParameter[] commandParameters,
out bool mustCloseConnection)
{
if (command ==
null)
throw new ArgumentNullException(
"command");
if (commandText ==
null || commandText.Length ==
0)
throw new ArgumentNullException(
"commandText");
// If the provided connection is not open, we will open it
if (connection.State !=
ConnectionState.Open)
{
mustCloseConnection =
true;
connection.Open();
}
else
{
mustCloseConnection =
false;
}
// 给命令分配一个数据库连接.
command.Connection =
connection;
// 设置命令文本(存储过程名或SQL语句)
command.CommandText =
commandText;
// 分配事务
if (transaction !=
null)
{
if (transaction.Connection ==
null)
throw new ArgumentException(
"The transaction was rollbacked or commited, please provide an open transaction.",
"transaction");
command.Transaction =
transaction;
}
// 设置命令类型.
command.CommandType =
commandType;
// 分配命令参数
if (commandParameters !=
null)
{
AttachParameters(command, commandParameters);
}
return;
}
#endregion 私有构造函数和方法结束
#region 数据库连接
/// <summary>
/// 一个有效的数据库连接字符串
/// </summary>
/// <returns></returns>
public static string GetConnSting()
{
return ConfigurationManager.ConnectionStrings[
"ConStr"].ConnectionString;
}
/// <summary>
/// 一个有效的数据库连接对象
/// </summary>
/// <returns></returns>
public static SqlConnection GetConnection()
{
SqlConnection Connection =
new SqlConnection(SqlHelper.GetConnSting());
return Connection;
}
#endregion
#region ExecuteNonQuery命令
/// <summary>
/// 执行指定连接字符串,类型的SqlCommand.
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders");
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
/// <param name="commandText">存储过程名称或SQL语句</param>
/// <returns>返回命令影响的行数</returns>
public static int ExecuteNonQuery(
string connectionString, CommandType commandType,
string commandText)
{
return ExecuteNonQuery(connectionString, commandType, commandText, (SqlParameter[])
null);
}
/// <summary>
/// 执行指定连接字符串,类型的SqlCommand.如果没有提供参数,不返回结果.
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
/// <param name="commandText">存储过程名称或SQL语句</param>
/// <param name="commandParameters">SqlParameter参数数组</param>
/// <returns>返回命令影响的行数</returns>
public static int ExecuteNonQuery(
string connectionString, CommandType commandType,
string commandText,
params SqlParameter[] commandParameters)
{
if (connectionString ==
null || connectionString.Length ==
0)
throw new ArgumentNullException(
"connectionString");
using (SqlConnection connection =
new SqlConnection(connectionString))
{
connection.Open();
return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
}
}
/// <summary>
/// 执行指定连接字符串的存储过程,将对象数组的值赋给存储过程参数,
/// 此方法需要在参数缓存方法中探索参数并生成参数.
/// </summary>
/// <remarks>
/// 这个方法没有提供访问输出参数和返回值.
/// 示例:
/// int result = ExecuteNonQuery(connString, "PublishOrders", 24, 36);
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串/param>
/// <param name="spName">存储过程名称</param>
/// <param name="parameterValues">分配到存储过程输入参数的对象数组</param>
/// <returns>返回受影响的行数</returns>
public static int ExecuteNonQuery(
string connectionString,
string spName,
params object[] parameterValues)
{
if (connectionString ==
null || connectionString.Length ==
0)
throw new ArgumentNullException(
"connectionString");
if (spName ==
null || spName.Length ==
0)
throw new ArgumentNullException(
"spName");
// 如果存在参数值
if ((parameterValues !=
null) && (parameterValues.Length >
0))
{
// 从探索存储过程参数(加载到缓存)并分配给存储过程参数数组.
SqlParameter[] commandParameters =
SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);
// 给存储过程参数赋值
AssignParameterValues(commandParameters, parameterValues);
return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName, commandParameters);
}
else
{
// 没有参数情况下
return ExecuteNonQuery(connectionString, CommandType.StoredProcedure, spName);
}
}
/// <summary>
/// 执行指定数据库连接对象的命令
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders");
/// </remarks>
/// <param name="connection">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <returns>返回影响的行数</returns>
public static int ExecuteNonQuery(SqlConnection connection, CommandType commandType,
string commandText)
{
return ExecuteNonQuery(connection, commandType, commandText, (SqlParameter[])
null);
}
/// <summary>
/// 执行指定数据库连接对象的命令
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connection">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">T存储过程名称或T-SQL语句</param>
/// <param name="commandParameters">SqlParamter参数数组</param>
/// <returns>返回影响的行数</returns>
public static int ExecuteNonQuery(SqlConnection connection, CommandType commandType,
string commandText,
params SqlParameter[] commandParameters)
{
if (connection ==
null)
throw new ArgumentNullException(
"connection");
// 创建SqlCommand命令,并进行预处理
SqlCommand cmd =
new SqlCommand();
bool mustCloseConnection =
false;
PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters,
out mustCloseConnection);
// Finally, execute the command
int retval =
cmd.ExecuteNonQuery();
// 清除参数,以便再次使用.
cmd.Parameters.Clear();
if (mustCloseConnection)
connection.Close();
return retval;
}
/// <summary>
/// 执行指定数据库连接对象的命令,将对象数组的值赋给存储过程参数.
/// </summary>
/// <remarks>
/// 此方法不提供访问存储过程输出参数和返回值
/// 示例:
/// int result = ExecuteNonQuery(conn, "PublishOrders", 24, 36);
/// </remarks>
/// <param name="connection">一个有效的数据库连接对象</param>
/// <param name="spName">存储过程名</param>
/// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
/// <returns>返回影响的行数</returns>
public static int ExecuteNonQuery(SqlConnection connection,
string spName,
params object[] parameterValues)
{
if (connection ==
null)
throw new ArgumentNullException(
"connection");
if (spName ==
null || spName.Length ==
0)
throw new ArgumentNullException(
"spName");
// 如果有参数值
if ((parameterValues !=
null) && (parameterValues.Length >
0))
{
// 从缓存中加载存储过程参数
SqlParameter[] commandParameters =
SqlHelperParameterCache.GetSpParameterSet(connection, spName);
// 给存储过程分配参数值
AssignParameterValues(commandParameters, parameterValues);
return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName, commandParameters);
}
else
{
return ExecuteNonQuery(connection, CommandType.StoredProcedure, spName);
}
}
/// <summary>
/// 执行带事务的SqlCommand.
/// </summary>
/// <remarks>
/// 示例.:
/// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders");
/// </remarks>
/// <param name="transaction">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <returns>返回影响的行数/returns>
public static int ExecuteNonQuery(SqlTransaction transaction, CommandType commandType,
string commandText)
{
return ExecuteNonQuery(transaction, commandType, commandText, (SqlParameter[])
null);
}
/// <summary>
/// 执行带事务的SqlCommand(指定参数).
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
/// </remarks>
/// <param name="transaction">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <param name="commandParameters">SqlParamter参数数组</param>
/// <returns>返回影响的行数</returns>
public static int ExecuteNonQuery(SqlTransaction transaction, CommandType commandType,
string commandText,
params SqlParameter[] commandParameters)
{
if (transaction ==
null)
throw new ArgumentNullException(
"transaction");
if (transaction !=
null && transaction.Connection ==
null)
throw new ArgumentException(
"The transaction was rollbacked or commited, please provide an open transaction.",
"transaction");
// 预处理
SqlCommand cmd =
new SqlCommand();
bool mustCloseConnection =
false;
PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);
// 执行
int retval =
cmd.ExecuteNonQuery();
// 清除参数集,以便再次使用.
cmd.Parameters.Clear();
return retval;
}
/// <summary>
/// 执行带事务的SqlCommand(指定参数值).
/// </summary>
/// <remarks>
/// 此方法不提供访问存储过程输出参数和返回值
/// 示例:
/// int result = ExecuteNonQuery(conn, trans, "PublishOrders", 24, 36);
/// </remarks>
/// <param name="transaction">一个有效的数据库连接对象</param>
/// <param name="spName">存储过程名</param>
/// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
/// <returns>返回受影响的行数</returns>
public static int ExecuteNonQuery(SqlTransaction transaction,
string spName,
params object[] parameterValues)
{
if (transaction ==
null)
throw new ArgumentNullException(
"transaction");
if (transaction !=
null && transaction.Connection ==
null)
throw new ArgumentException(
"The transaction was rollbacked or commited, please provide an open transaction.",
"transaction");
if (spName ==
null || spName.Length ==
0)
throw new ArgumentNullException(
"spName");
// 如果有参数值
if ((parameterValues !=
null) && (parameterValues.Length >
0))
{
// 从缓存中加载存储过程参数,如果缓存中不存在则从数据库中检索参数信息并加载到缓存中. ()
SqlParameter[] commandParameters =
SqlHelperParameterCache.GetSpParameterSet(transaction.Connection, spName);
// 给存储过程参数赋值
AssignParameterValues(commandParameters, parameterValues);
// 调用重载方法
return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName, commandParameters);
}
else
{
// 没有参数值
return ExecuteNonQuery(transaction, CommandType.StoredProcedure, spName);
}
}
#endregion ExecuteNonQuery方法结束
#region ExecuteDataset方法
/// <summary>
/// 执行指定数据库连接字符串的命令,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders");
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(
string connectionString, CommandType commandType,
string commandText)
{
return ExecuteDataset(connectionString, commandType, commandText, (SqlParameter[])
null);
}
/// <summary>
/// 执行指定数据库连接字符串的命令,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <param name="commandParameters">SqlParamters参数数组</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(
string connectionString, CommandType commandType,
string commandText,
params SqlParameter[] commandParameters)
{
if (connectionString ==
null || connectionString.Length ==
0)
throw new ArgumentNullException(
"connectionString");
// 创建并打开数据库连接对象,操作完成释放对象.
using (SqlConnection connection =
new SqlConnection(connectionString))
{
connection.Open();
// 调用指定数据库连接字符串重载方法.
return ExecuteDataset(connection, commandType, commandText, commandParameters);
}
}
/// <summary>
/// 执行指定数据库连接字符串的命令,直接提供参数值,返回DataSet.
/// </summary>
/// <remarks>
/// 此方法不提供访问存储过程输出参数和返回值.
/// 示例:
/// DataSet ds = ExecuteDataset(connString, "GetOrders", 24, 36);
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="spName">存储过程名</param>
/// <param name="parameterValues">分配给存储过程输入参数的对象数组</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(
string connectionString,
string spName,
params object[] parameterValues)
{
if (connectionString ==
null || connectionString.Length ==
0)
throw new ArgumentNullException(
"connectionString");
if (spName ==
null || spName.Length ==
0)
throw new ArgumentNullException(
"spName");
if ((parameterValues !=
null) && (parameterValues.Length >
0))
{
// 从缓存中检索存储过程参数
SqlParameter[] commandParameters =
SqlHelperParameterCache.GetSpParameterSet(connectionString, spName);
// 给存储过程参数分配值
AssignParameterValues(commandParameters, parameterValues);
return ExecuteDataset(connectionString, CommandType.StoredProcedure, spName, commandParameters);
}
else
{
return ExecuteDataset(connectionString, CommandType.StoredProcedure, spName);
}
}
/// <summary>
/// 执行指定数据库连接对象的命令,返回DataSet.
