using System;
using System.Configuration;
using System.Data;
using System.Collections;
using Oracle.DataAccess.Client;namespace OracleHelper
{/// <summary>///Oracle数据库操作帮助类/// </summary>public abstract class OracleHelper{//从配置文件中读取配置好的连接字符串public static readonly string ConnectionStringLocalTransaction = ConfigurationManager.ConnectionStrings["OraConnString1"].ConnectionString;public static readonly string ConnectionStringInventoryDistributedTransaction = ConfigurationManager.ConnectionStrings["OraConnString2"].ConnectionString;public static readonly string ConnectionStringOrderDistributedTransaction = ConfigurationManager.ConnectionStrings["OraConnString3"].ConnectionString;public static readonly string ConnectionStringProfile = ConfigurationManager.ConnectionStrings["OraProfileConnString"].ConnectionString;public static readonly string ConnectionStringMembership = ConfigurationManager.ConnectionStrings["OraMembershipConnString"].ConnectionString;//为缓存的参数创建一个hashtableprivate static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());/// <summary>/// 增删改操作使用此方法/// </summary>/// <param name="connString">连接字符串</param>/// <param name="cmdType">命令类型（sql语句或者存储过程）</param>/// <param name="cmdText">要执行的sql语句或者存储过程名称</param>/// <param name="commandParameters">执行所需的一些参数</param>/// <returns>返回受影响的行数</returns>public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters){// 创建一个OracleCommandOracleCommand cmd = new OracleCommand();//创建一个OracleConnectionusing (OracleConnection connection = new OracleConnection(connectionString)){//调用静态方法PrepareCommand完成赋值操作PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);//执行命令返回int val = cmd.ExecuteNonQuery();//清空参数
                cmd.Parameters.Clear();return val;}}/// <summary>/// 增删改操作使用此方法（需要一个存在的事务参数）/// </summary>/// <param name="trans">一个存在的事务</param>/// <param name="commandType">命令类型（sql或者存储过程）</param>/// <param name="commandText">sql语句或者存储过程名称</param>/// <param name="commandParameters">命令所需参数数组</param>/// <returns>返回受影响的行数</returns>public static int ExecuteNonQuery(OracleTransaction trans, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters){// 创建一个OracleCommandOracleCommand cmd = new OracleCommand();//调用静态方法PrepareCommand完成赋值操作
            PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);//执行命令返回int val = cmd.ExecuteNonQuery();//清空参数
            cmd.Parameters.Clear();return val;}/// <summary>/// 增删改操作使用此方法（需要一个存在的连接）/// </summary> /// <param name="conn">一个存在的OracleConnection参数</param>/// <param name="commandType">命令类型（sql或者存储过程）</param>/// <param name="commandText">sql语句或者存储过程名称</param>/// <param name="commandParameters">命令所需参数数组</param>/// <returns>返回受影响的行数</returns>public static int ExecuteNonQuery(OracleConnection connection, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters){// 创建一个OracleCommandOracleCommand cmd = new OracleCommand();//调用静态方法PrepareCommand完成赋值操作PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);//执行命令返回int val = cmd.ExecuteNonQuery();//清空参数
            cmd.Parameters.Clear();return val;}/// <summary>/// 查询返回一个结果集/// </summary>/// <param name="connString">连接字符串</param>//// <param name="commandType">命令类型（sql或者存储过程）</param>/// <param name="commandText">sql语句或者存储过程名称</param>/// <param name="commandParameters">命令所需参数数组</param>/// <returns></returns>public static OracleDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters){// 创建一个OracleCommandOracleCommand cmd = new OracleCommand();// 创建一个OracleConnectionOracleConnection conn = new OracleConnection(connectionString);try{//调用静态方法PrepareCommand完成赋值操作PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);//执行查询OracleDataReader odr = cmd.ExecuteReader(CommandBehavior.CloseConnection);//清空参数
                cmd.Parameters.Clear();return odr;}catch{//如果发生异常，关闭连接，并且向上抛出异常
                conn.Close();throw;}}/// <summary>/// 执行语句返回的是单行单列的结果 /// </summary>/// <param name="connectionString">连接字符串</param>/// <param name="commandType">命令类型（sql或者存储过程）</param>/// <param name="commandText">sql语句或者存储过程名称</param>/// <param name="commandParameters">命令所需参数数组</param>/// <returns>返回是第一行第一列的结果（object类型）请使用Covert.to进行类型转换</returns>public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters){// 创建一个OracleCommandOracleCommand cmd = new OracleCommand();// 创建一个OracleConnectionusing (OracleConnection conn = new OracleConnection(connectionString)){//调用静态方法PrepareCommand完成赋值操作PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);//执行查询object val = cmd.ExecuteScalar();//清空参数
                cmd.Parameters.Clear();return val;}}///    <summary>///    执行语句返回的是单行单列的结果（有指定的事务参数）///    </summary>///    <param name="transaction">一个存在的事务参数</param>///    <param name="commandType">命令类型（sql或者存储过程）</param>///    <param name="commandText">sql语句或者存储过程名称</param>///    <param name="commandParameters">命令所需参数数组</param>///    <returns>返回是第一行第一列的结果（object类型）请使用Covert.to进行类型转换</returns>public static object ExecuteScalar(OracleTransaction transaction, CommandType commandType, string commandText, params OracleParameter[] commandParameters){//如果传入的事务是空值，抛出异常if (transaction == null)throw new ArgumentNullException("transaction");//如果传入的事务无连接，抛出异常（无连接，说明传入的事务参数是已经提交过或者回滚了的事务）if (transaction != null && transaction.Connection == null)throw new ArgumentException("The transaction was rollbacked    or commited, please    provide    an open    transaction.", "transaction");// 创建一个OracleCommandOracleCommand cmd = new OracleCommand();//调用静态方法PrepareCommand完成赋值操作
            PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters);//执行查询object retval = cmd.ExecuteScalar();//清空参数
            cmd.Parameters.Clear();return retval;}/// <summary>///   执行语句返回的是单行单列的结果（有指定的连接参数）/// </summary>/// <param name="conn">一个存在的连接参数</param>/// <param name="commandType">命令类型（sql或者存储过程）</param>/// <param name="commandText">sql语句或者存储过程名称</param>/// <param name="commandParameters">命令所需参数数组</param>/// <returns>返回是第一行第一列的结果（object类型）请使用Covert.to进行类型转换</returns>public static object ExecuteScalar(OracleConnection connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters){// 创建一个OracleCommandOracleCommand cmd = new OracleCommand();//调用静态方法PrepareCommand完成赋值操作PrepareCommand(cmd, connectionString, null, cmdType, cmdText, commandParameters);//执行查询object val = cmd.ExecuteScalar();//清空参数
            cmd.Parameters.Clear();return val;}/// <summary>/// Add a set of parameters to the cached/// </summary>/// <param name="cacheKey">Key value to look up the parameters</param>/// <param name="commandParameters">Actual parameters to cached</param>public static void CacheParameters(string cacheKey, params OracleParameter[] commandParameters){parmCache[cacheKey] = commandParameters;}/// <summary>/// 从缓存中获取参数/// </summary>/// <param name="cacheKey">look up 中的cachekey</param>/// <returns></returns>public static OracleParameter[] GetCachedParameters(string cacheKey){OracleParameter[] cachedParms = (OracleParameter[])parmCache[cacheKey];if (cachedParms == null)return null;// 如果缓存中有此参数OracleParameter[] clonedParms = new OracleParameter[cachedParms.Length];// 返回参数的copyfor (int i = 0, j = cachedParms.Length; i < j; i++)clonedParms[i] = (OracleParameter)((ICloneable)cachedParms[i]).Clone();return clonedParms;}/// <summary>/// 一个静态的预处理函数/// </summary>/// <param name="cmd">存在的OracleCommand对象</param>/// <param name="conn">存在的OracleConnection对象</param>/// <param name="trans">存在的OracleTransaction对象</param>/// <param name="cmdType">命令类型（sql或者存在过程）</param>/// <param name="cmdText">sql语句或者存储过程名称</param>/// <param name="commandParameters">Parameters for the command</param>private static void PrepareCommand(OracleCommand cmd, OracleConnection conn, OracleTransaction trans, CommandType cmdType, string cmdText, OracleParameter[] commandParameters){//如果连接未打开，先打开连接if (conn.State != ConnectionState.Open)conn.Open();//未要执行的命令设置参数cmd.Connection = conn;cmd.CommandText = cmdText;cmd.CommandType = cmdType;//如果传入了事务，需要将命令绑定到指定的事务上去if (trans != null)cmd.Transaction = trans;//将传入的参数信息赋值给命令参数if (commandParameters != null){cmd.Parameters.AddRange(commandParameters);}}}
}