oracleHelper 操作帮助类

 using System;
 using System.Configuration;
 using System.Data;
 using System.Collections;
 using Oracle.DataAccess.Client;

 namespace Cont.DAL.Leave
 {
     /// <summary>
     ///Oracle数据库操作帮助类
     /// </summary>
     public class OracleHelper
     {
         //从配置文件中读取配置好的连接字符串
         private static  OracleConnection conn = new OracleConnection(ConfigurationManager.ConnectionStrings["conn"].ToString());
         private static OracleTransaction tran = null;

         /// <summary>
         /// 返回受影响的行数
         /// </summary>
         /// <param name="sql">sql语句</param>
         /// <returns></returns>
         public static int NonQuery(string sql)
         {
             try
             {
                 OracleCommand cmd = new OracleCommand(sql, conn);
                 int i = cmd.ExecuteNonQuery();
                 return i;//将受影响的行数返回
             }
             catch (Exception se)
             {
                 throw se;
             }

         }
         /// <summary>
         /// 返回一个临时表数据，一般执行显示表中多条数据操作  select
         /// </summary>
         /// <param name="sql">要执行的查询sql语句</param>
         /// <returns>返回一个DataTable</returns>
         public static DataTable GetTable(string sql)
         {
             try
             {
                 conn.Open();
                 OracleDataAdapter sda = new OracleDataAdapter(sql, conn);
                 DataTable dt = new DataTable();
                 sda.Fill(dt);
                 return dt;
             }
             catch (Exception se)
             {
                 throw se;
             }
             finally
             {
                 conn.Close();
             }

         }
         /// <summary>
         /// 执行查询操作，返回一个结果集
         /// </summary>
         /// <param name="sql">要执行的sql语句</param>
         /// <returns>返回一个读取器</returns>
         public static OracleDataReader Reader(string sql)
         {
             try
             {
                 conn.Open();
                 OracleCommand cmd = new OracleCommand(sql, conn);
                 OracleDataReader sdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);//读取器和数据源此处不能被关闭
                 return sdr;
             }
             catch (Exception se)
             {
                 throw se;
             }
         }
         /// <summary>
         /// 执行查询操作，返回一个单值，一般执行根据名称找编号或执行聚合函数
         /// </summary>
         /// <param name="sql">要执行的sql查询语句</param>
         /// <returns>返回一个object类型</returns>
         public static object Scalar(string sql)
         {
             try
             {
                 conn.Open();
                 OracleCommand cmd = new OracleCommand(sql, conn);
                 object obj = cmd.ExecuteScalar();
                 return obj;
             }
             catch (Exception se)
             {
                 throw se;
             }
             finally
             {
                 conn.Close();
             }
         }

         /// <summary>
         ///开始事务
         /// </summary>
         public static void BeginTran()
         {
             conn.Open();
             tran = conn.BeginTransaction();
         }

         /// <summary>
         /// 提交事务
         /// </summary>
         public static void CommitTran()
         {
             tran.Commit();
             tran.Dispose();
             conn.Close();
             tran = null;
         }

         /// <summary>
         /// 回滚
         /// </summary>
         public static void RollbackTran()
         {
             tran.Rollback();
             tran.Dispose();
             conn.Close();
             tran = null;
         }
     }
 }