using System;using System.Data;using System.Collections.Generic;using System.Configuration;using System.Data.OracleClient;using System.Text;using System.IO;/// <summary>/// Oracle数据库操作类/// </summary>internal static class OracleHelper{ //数据库连接字符串 private readonly static string connstr = ConfigurationManager.ConnectionStrings["ConnectionStrings"].ConnectionString; /// <summary> /// 执行数据库查询操作,返回受影响的行数 /// </summary> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前查询操作影响的数据行数</returns> internal static int ExecuteNonQuery(string cmdText, params OracleParameter[] commandParameters) { OracleCommand command = new OracleCommand(); OracleConnection connection = new OracleConnection(connstr); int result = 0; try { PrepareCommand(command, connection, null,CommandType.Text, cmdText, commandParameters); result = command.ExecuteNonQuery(); command.Parameters.Clear(); } catch { throw; } finally { command.Dispose(); connection.Close(); connection.Dispose(); } return result; } /// <summary> /// 执行数据库事务查询操作,返回受影响的行数 /// </summary> /// <param name="transaction">数据库事务对象</param> /// <param name="cmdType">Command类型</param> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前事务查询操作影响的数据行数</returns> internal static int ExecuteNonQuery(OracleTransaction transaction, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) { OracleCommand command = new OracleCommand(); OracleConnection connection = transaction.Connection; int result = 0; try { PrepareCommand(command, connection, transaction, cmdType, cmdText, commandParameters); result = command.ExecuteNonQuery(); command.Parameters.Clear(); } catch { throw; } finally { transaction.Dispose(); command.Dispose(); connection.Close(); connection.Dispose(); } return result; } /// <summary> /// 执行数据库查询操作,返回受影响的行数 /// </summary> /// <param name="connection">Oracle数据库连接对象</param> /// <param name="cmdType">Command类型</param> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前查询操作影响的数据行数</returns> internal static int ExecuteNonQuery(OracleConnection connection, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) { if (connection == null) throw new ArgumentNullException("当前数据库连接不存在"); OracleCommand command = new OracleCommand(); int result = 0; try { PrepareCommand(command, connection, null, cmdType, cmdText, commandParameters); result = command.ExecuteNonQuery(); command.Parameters.Clear(); } catch { throw; } finally { command.Dispose(); connection.Close(); connection.Dispose(); } return result; } /// <summary> /// 执行数据库查询操作,返回OracleDataReader类型的内存结果集 /// </summary> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前查询操作返回的OracleDataReader类型的内存结果集</returns> internal static OracleDataReader ExecuteReader(string cmdText, params OracleParameter[] commandParameters) { OracleCommand command = new OracleCommand(); OracleConnection connection = new OracleConnection(connstr); OracleDataReader reader = null; try { PrepareCommand(command, connection, null,CommandType.Text, cmdText, commandParameters); reader = command.ExecuteReader(CommandBehavior.CloseConnection); command.Parameters.Clear(); return reader; } catch { command.Dispose(); connection.Close(); throw; } } /// <summary> /// 执行数据库查询操作,返回DataSet类型的结果集 /// </summary> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前查询操作返回的DataSet类型的结果集</returns> internal static DataSet ExecuteDataSet(string cmdText, params OracleParameter[] commandParameters) { OracleCommand command = new OracleCommand(); OracleConnection connection = new OracleConnection(connstr); DataSet dataset = null; try { PrepareCommand(command, connection, null,CommandType.Text, cmdText, commandParameters); OracleDataAdapter adapter = new OracleDataAdapter(); adapter.SelectCommand = command; dataset = new DataSet(); adapter.Fill(dataset); command.Parameters.Clear(); } catch { throw; } finally { command.Dispose(); connection.Close(); connection.Dispose(); } return dataset; } /// <summary> /// 执行数据库查询操作,返回DataTable类型的结果集 /// </summary> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前查询操作返回的DataTable类型的结果集</returns> internal static DataTable ExecuteDataTable(string cmdText, params OracleParameter[] commandParameters) { OracleCommand command = new OracleCommand(); OracleConnection connection = new OracleConnection(connstr); DataTable table = null; try { PrepareCommand(command, connection, null,CommandType.Text, cmdText, commandParameters); OracleDataAdapter adapter = new OracleDataAdapter(); adapter.SelectCommand = command; table = new DataTable(); adapter.Fill(table); command.Parameters.Clear(); } catch { throw; } finally { command.Dispose(); connection.Close(); connection.Dispose(); } return table; } /// <summary> /// 执行数据库查询操作,返回结果集中位于第一行第一列的Object类型的值 /// </summary> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前查询操作返回的结果集中位于第一行第一列的Object类型的值</returns> internal static object ExecuteScalar(string cmdText, params OracleParameter[] commandParameters) { OracleCommand command = new OracleCommand(); OracleConnection connection = new OracleConnection(connstr); object result = null; try { PrepareCommand(command, connection, null,CommandType.Text, cmdText, commandParameters); result = command.ExecuteScalar(); command.Parameters.Clear(); } catch { throw; } finally { command.Dispose(); connection.Close(); connection.Dispose(); } return result; } /// <summary> /// 执行数据库事务查询操作,返回结果集中位于第一行第一列的Object类型的值 /// </summary> /// <param name="transaction">一个已存在的数据库事务对象</param> /// <param name="commandType">命令类型</param> /// <param name="commandText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前事务查询操作返回的结果集中位于第一行第一列的Object类型的值</returns> internal static object ExecuteScalar(OracleTransaction transaction, CommandType commandType, string commandText, params OracleParameter[] commandParameters) { if (transaction == null) throw new ArgumentNullException("当前数据库事务不存在"); OracleConnection connection = transaction.Connection; if (connection == null) throw new ArgumentException("当前事务所在的数据库连接不存在"); OracleCommand command = new OracleCommand(); object result = null; try { PrepareCommand(command, connection, transaction, commandType, commandText, commandParameters); result = command.ExecuteScalar(); command.Parameters.Clear(); } catch { throw; } finally { transaction.Dispose(); command.Dispose(); connection.Close(); connection.Dispose(); } return result; } /// <summary> /// 执行数据库查询操作,返回结果集中位于第一行第一列的Object类型的值 /// </summary> /// <param name="connection">数据库连接对象</param> /// <param name="cmdType">Command类型</param> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> /// <returns>当前查询操作返回的结果集中位于第一行第一列的Object类型的值</returns> internal static object ExecuteScalar(OracleConnection connection, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) { if (connection == null) throw new ArgumentException("当前数据库连接不存在"); OracleCommand command = new OracleCommand(); object result = null; try { PrepareCommand(command, connection, null, cmdType, cmdText, commandParameters); result = command.ExecuteScalar(); command.Parameters.Clear(); } catch { throw; } finally { command.Dispose(); connection.Close(); connection.Dispose(); } return result; } /// <summary> /// 执行数据库命令前的准备工作 /// </summary> /// <param name="command">Command对象</param> /// <param name="connection">数据库连接对象</param> /// <param name="trans">事务对象</param> /// <param name="cmdType">Command类型</param> /// <param name="cmdText">Oracle存储过程名称或PL/SQL命令</param> /// <param name="commandParameters">命令参数集合</param> private static void PrepareCommand(OracleCommand command, OracleConnection connection, OracleTransaction trans, CommandType cmdType, string cmdText, OracleParameter[] commandParameters) { if (connection.State != ConnectionState.Open) connection.Open(); command.Connection = connection; command.CommandText = cmdText; command.CommandType = cmdType; if (trans != null) command.Transaction = trans; if (commandParameters != null) { foreach (OracleParameter parm in commandParameters) command.Parameters.Add(parm); } } /// <summary> /// 将.NET日期时间类型转化为Oracle兼容的日期时间格式字符串 /// </summary> /// <param name="date">.NET日期时间类型对象</param> /// <returns>Oracle兼容的日期时间格式字符串（如该字符串：TO_DATE('2007-12-1','YYYY-MM-DD')）</returns> internal static string GetOracleDateFormat(DateTime date) { return "TO_DATE('" + date.ToString("yyyy-M-dd") + "','YYYY-MM-DD')"; } /// <summary> /// 将.NET日期时间类型转化为Oracle兼容的日期格式字符串 /// </summary> /// <param name="date">.NET日期时间类型对象</param> /// <param name="format">Oracle日期时间类型格式化限定符</param> /// <returns>Oracle兼容的日期时间格式字符串（如该字符串：TO_DATE('2007-12-1','YYYY-MM-DD')）</returns> internal static string GetOracleDateFormat(DateTime date, string format) { if (format == null || format.Trim() == "") format = "YYYY-MM-DD"; return "TO_DATE('" + date.ToString("yyyy-M-dd") + "','" + format + "')"; } /// <summary> /// 将指定的关键字处理为模糊查询时的合法参数值 /// </summary> /// <param name="source">待处理的查询关键字</param> /// <returns>过滤后的查询关键字</returns> internal static string HandleLikeKey(string source) { if (source == null || source.Trim() == "") return null; source = source.Replace("[", "[]]"); source = source.Replace("_", "[_]"); source = source.Replace("%", "[%]"); return ("%" + source + "%"); } /// <summary> /// 将文本内容写入到数据库的CLOB字段中（不可用：报连接被关闭的异常） /// </summary> /// <param name="connectionString">数据库连接字符串</param> /// <param name="table">数据库表名称</param> /// <param name="where">指定的WHERE条件语句</param> /// <param name="clobField">CLOB字段的名称</param> /// <param name="content">要写入的文本内容</param> internal static void WriteCLOB(string table, string where, string clobField, string content) { if (String.IsNullOrEmpty(connstr) || String.IsNullOrEmpty(table) || String.IsNullOrEmpty(clobField)) return; using (OracleConnection connection = new OracleConnection(connstr)) { OracleCommand command = null; try { connection.Open(); command = connection.CreateCommand(); command.CommandText = "SELECT " + clobField + " FROM " + table + " WHERE " + where + " FOR UPDATE"; OracleDataReader reader = command.ExecuteReader(); if (reader != null && reader.HasRows) { reader.Read(); command.Transaction = command.Connection.BeginTransaction(); OracleLob lob = reader.GetOracleLob(0); byte[] buffer = Encoding.Unicode.GetBytes(content); if (lob != OracleLob.Null) lob.Erase(); lob.Write(buffer, 0, ((buffer.Length % 2 == 0) ? buffer.Length : (buffer.Length - 1))); command.Transaction.Commit(); reader.Close(); } } catch { command.Transaction.Rollback(); throw; } finally { command.Dispose(); connection.Close(); connection.Dispose(); } } } /// <summary> /// 从数据库中读取CLOB字段的内容并进行输出 /// </summary> /// <param name="connectionString">数据库连接字符串</param> /// <param name="table">数据库表名称</param> /// <param name="where">指定的WHERE条件语句</param> /// <param name="clobField">CLOB字段的名称</param> /// <param name="output">保存内容输出的字符串变量</param> internal static void ReadCLOB(string connectionString, string table, string where, string clobField, ref string output) { if (String.IsNullOrEmpty(connectionString) || String.IsNullOrEmpty(table) || String.IsNullOrEmpty(clobField)) return; using (OracleConnection connection = new OracleConnection(connectionString)) { OracleCommand command = null; StreamReader stream = null; try { connection.Open(); command = connection.CreateCommand(); command.CommandText = "SELECT " + clobField + " FROM " + table + " WHERE " + where; OracleDataReader reader = command.ExecuteReader(); if (reader != null && reader.HasRows) { reader.Read(); command.Transaction = command.Connection.BeginTransaction(); OracleLob lob = reader.GetOracleLob(0); if (lob != OracleLob.Null) { stream = new StreamReader(lob, Encoding.Unicode); output = stream.ReadToEnd().Trim(); command.Transaction.Commit(); reader.Close(); } } } catch { command.Transaction.Rollback(); throw; } finally { stream.Close(); command.Dispose(); connection.Close(); connection.Dispose(); } } }}
