一个操作oracle的c#类 含分页

有别于以前的一个OracleHelper，这个版各有所长，MARK下。

using System;
using System.Data;
using System.Data.OracleClient;
using System.Web.UI.WebControls; namespace SiFenManager.Util
{
/// <summary>
/// 数据库通用操作类
/// </summary>
public class Database
{
protected  OracleConnection con;//连接对象

public Database()
{
con=new OracleConnection(DafangFramework.AppConfig.DataBaseConnectionString);
}
public Database(string constr)
{
con=new OracleConnection(constr);
}
#region 打开数据库连接
/// <summary>
/// 打开数据库连接
/// </summary>
  private  void Open()
{
//打开数据库连接
   if(con.State==ConnectionState.Closed)
{
try
{
//打开数据库连接
     con.Open();
}
catch(Exception e)
{
throw e;
}
}
}
#endregion
#region 关闭数据库连接
/// <summary>
/// 关闭数据库连接
/// </summary>
  private  void Close()
{
//判断连接的状态是否已经打开
   if(con.State==ConnectionState.Open)
{
con.Close();
}
}
#endregion
#region 执行查询语句，返回OracleDataReader ( 注意：调用该方法后，一定要对OracleDataReader进行Close )
/// <summary>
/// 执行查询语句，返回OracleDataReader ( 注意：调用该方法后，一定要对OracleDataReader进行Close )
/// </summary>
/// <param name="sql">查询语句</param>
/// <returns>OracleDataReader</returns>
  public  OracleDataReader ExecuteReader(string sql)
{
OracleDataReader myReader;
Open();
OracleCommand cmd = new OracleCommand(sql, con);
myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
return myReader;
}
#endregion
#region 执行带参数的SQL语句
/// <summary>
/// 执行SQL语句，返回影响的记录数
/// </summary>
/// <param name="sql">SQL语句</param>
/// <returns>影响的记录数</returns>
  public  int ExecuteSql(string sql, params OracleParameter[] cmdParms)
{
OracleCommand cmd = new OracleCommand();
{
try
{
PrepareCommand(cmd, con, null, sql, cmdParms);
int rows = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return rows;
}
catch (System.Data.OracleClient.OracleException e)
{
throw e;
}
}
}
#endregion
#region 执行带参数的SQL语句
/// <summary>
/// 执行不带参数的SQL语句
/// </summary>
/// <param name="sql">SQL语句</param>
  public  void ExecuteSql(string sql)
{
OracleCommand cmd = new OracleCommand(sql,con);
try
{
Open();
cmd.ExecuteNonQuery();
Close();
}
catch (System.Data.OracleClient.OracleException e)
{
Close();
throw e;
}
}
#endregion
#region 执行SQL语句，返回数据到DataSet中
/// <summary>
/// 执行SQL语句，返回数据到DataSet中
/// </summary>
/// <param name="sql">sql语句</param>
/// <returns>返回DataSet</returns>
  public  DataSet GetDataSet(string sql)
{
DataSet ds=new DataSet();
try
{
Open();//打开数据连接
    OracleDataAdapter adapter=new OracleDataAdapter(sql,con);
adapter.Fill(ds);
}
catch//(Exception ex)
   {
}
finally
{
Close();//关闭数据库连接
   }
return ds;
}
#endregion
#region 执行SQL语句，返回数据到自定义DataSet中
/// <summary>
/// 执行SQL语句，返回数据到DataSet中
/// </summary>
/// <param name="sql">sql语句</param>
/// <param name="DataSetName">自定义返回的DataSet表名</param>
/// <returns>返回DataSet</returns>
  public  DataSet GetDataSet(string sql,string DataSetName)
{
DataSet ds=new DataSet();
Open();//打开数据连接
   OracleDataAdapter adapter=new OracleDataAdapter(sql,con);
adapter.Fill(ds,DataSetName);
Close();//关闭数据库连接
   return ds;
}
#endregion
#region 执行Sql语句,返回带分页功能的自定义dataset
/// <summary>
/// 执行Sql语句,返回带分页功能的自定义dataset
/// </summary>
/// <param name="sql">Sql语句</param>
/// <param name="PageSize">每页显示记录数</param>
/// <param name="CurrPageIndex">当前页</param>
/// <param name="DataSetName">返回dataset表名</param>
/// <returns>返回DataSet</returns>
  public  DataSet GetDataSet(string sql,int PageSize,int CurrPageIndex,string DataSetName)
{
DataSet ds=new DataSet();
Open();//打开数据连接
   OracleDataAdapter adapter=new OracleDataAdapter(sql,con);
adapter.Fill(ds,PageSize * (CurrPageIndex - ), PageSize,DataSetName);
Close();//关闭数据库连接
   return ds;
}
#endregion
#region 执行SQL语句，返回记录总数
/// <summary>
/// 执行SQL语句，返回记录总数
/// </summary>
/// <param name="sql">sql语句</param>
/// <returns>返回记录总条数</returns>
  public  int GetRecordCount(string sql)
{
int recordCount = ;
Open();//打开数据连接
   OracleCommand command = new OracleCommand(sql,con);
OracleDataReader dataReader = command.ExecuteReader();
while(dataReader.Read())
{
recordCount++;
}
dataReader.Close();
Close();//关闭数据库连接
   return recordCount;
}
#endregion

#region 统计某表记录总数
/// <summary>
/// 统计某表记录总数
/// </summary>
/// <param name="KeyField">主键/索引键</param>
/// <param name="TableName">数据库.用户名.表名</param>
/// <param name="Condition">查询条件</param>
/// <returns>返回记录总数</returns>
  public  int GetRecordCount(string keyField, string tableName, string condition)
{
int RecordCount = ;
string sql = "select count(" + keyField + ") as count from " + tableName + " " + condition;
DataSet ds = GetDataSet(sql);
if (ds.Tables[].Rows.Count > )
{
RecordCount =Convert.ToInt32(ds.Tables[].Rows[][]);
}
ds.Clear();
ds.Dispose();
return RecordCount;
}
/// <summary>
/// 统计某表记录总数
/// </summary>
/// <param name="Field">可重复的字段</param>
/// <param name="tableName">数据库.用户名.表名</param>
/// <param name="condition">查询条件</param>
/// <param name="flag">字段是否主键</param>
/// <returns>返回记录总数</returns>
  public  int GetRecordCount(string Field, string tableName, string condition, bool flag)
{
int RecordCount = ;
if (flag)
{
RecordCount = GetRecordCount(Field, tableName, condition);
}
else
{
string sql = "select count(distinct(" + Field + ")) as count from " + tableName + " " + condition;
DataSet ds = GetDataSet(sql);
if (ds.Tables[].Rows.Count > )
{
RecordCount = Convert.ToInt32(ds.Tables[].Rows[][]);
}
ds.Clear();
ds.Dispose();
}
return RecordCount;
}
#endregion
#region 统计某表分页总数
/// <summary>
/// 统计某表分页总数
/// </summary>
/// <param name="keyField">主键/索引键</param>
/// <param name="tableName">表名</param>
/// <param name="condition">查询条件</param>
/// <param name="pageSize">页宽</param>
/// <param name="RecordCount">记录总数</param>
/// <returns>返回分页总数</returns>
  public  int GetPageCount(string keyField, string tableName, string condition, int pageSize, int RecordCount)
{
int PageCount = ;
PageCount = (RecordCount % pageSize) >  ? (RecordCount / pageSize) +  : RecordCount / pageSize;
if (PageCount < ) PageCount = ;
return PageCount;
}
/// <summary>
/// 统计某表分页总数
/// </summary>
/// <param name="keyField">主键/索引键</param>
/// <param name="tableName">表名</param>
/// <param name="condition">查询条件</param>
/// <param name="pageSize">页宽</param>
/// <returns>返回页面总数</returns>
  public  int GetPageCount(string keyField, string tableName, string condition, int pageSize, ref int RecordCount)
{
RecordCount = GetRecordCount(keyField, tableName, condition);
return GetPageCount(keyField, tableName, condition, pageSize, RecordCount);
}
/// <summary>
/// 统计某表分页总数
/// </summary>
/// <param name="Field">可重复的字段</param>
/// <param name="tableName">表名</param>
/// <param name="condition">查询条件</param>
/// <param name="pageSize">页宽</param>
/// <param name="flag">是否主键</param>
/// <returns>返回页页总数</returns>
  public  int GetPageCount(string Field, string tableName, string condition, ref int RecordCount, int pageSize, bool flag)
{
RecordCount = GetRecordCount(Field, tableName, condition, flag);
return GetPageCount(Field, tableName, condition, pageSize, ref RecordCount);
}
#endregion 

#region Sql分页函数
/// <summary>
/// 构造分页查询SQL语句
/// </summary>
/// <param name="KeyField">主键</param>
/// <param name="FieldStr">所有需要查询的字段(field1,field2...)</param>
/// <param name="TableName">库名.拥有者.表名</param>
/// <param name="where">查询条件1(where ...)</param>
/// <param name="order">排序条件2(order by ...)</param>
/// <param name="CurrentPage">当前页号</param>
/// <param name="PageSize">页宽</param>
/// <returns>SQL语句</returns>
  public  string JoinPageSQL(string KeyField, string FieldStr, string TableName, string Where, string Order, int CurrentPage, int PageSize)
{
string sql = null;
if (CurrentPage == )
{
sql = "select  " + CurrentPage * PageSize + " " + FieldStr + " from " + TableName + " " + Where + " " + Order + " ";
}
else
{
sql = "select * from (";
sql += "select  " + CurrentPage * PageSize + " " + FieldStr + " from " + TableName + " " + Where + " " + Order + ") a ";
sql += "where " + KeyField + " not in (";
sql += "select  " + (CurrentPage - ) * PageSize + " " + KeyField + " from " + TableName + " " + Where + " " + Order + ")";
}
return sql;
}
/// <summary>
/// 构造分页查询SQL语句
/// </summary>
/// <param name="Field">字段名(非主键)</param>
/// <param name="TableName">库名.拥有者.表名</param>
/// <param name="where">查询条件1(where ...)</param>
/// <param name="order">排序条件2(order by ...)</param>
/// <param name="CurrentPage">当前页号</param>
/// <param name="PageSize">页宽</param>
/// <returns>SQL语句</returns>
  public  string JoinPageSQL(string Field, string TableName,string Where, string Order, int CurrentPage, int PageSize)
{
string sql = null;
if (CurrentPage == )
{
sql = "select rownum " + CurrentPage * PageSize + " " + Field + " from " + TableName + " " + Where + " " + Order + " group by " + Field;
}
else
{
sql = "select * from (";
sql += "select rownum " + CurrentPage * PageSize + " " + Field + " from " + TableName + " " + Where + " " + Order + " group by " + Field + " ) a ";
sql += "where " + Field + " not in (";
sql += "select rownum " + (CurrentPage - ) * PageSize + " " + Field + " from " + TableName + " " + Where + " " + Order + " group by " + Field + ")";
}
return sql;
}
#endregion
#region 根据系统时间动态生成各种查询语句(现已经注释掉，以备以后使用)
//  #region 根据查询时间的条件，动态生成查询语句
//  /// <summary>
//  /// 根据查询时间的条件，动态生成查询语句
//  /// </summary>
//  /// <param name="starttime">开始时间</param>
//  /// <param name="endtime">结束时间</param>
//  /// <param name="dw">单位</param>
//  /// <param name="startxsl">开始线损率</param>
//  /// <param name="endxsl">结束线损率</param>
//  /// <param name="danwei">单位字段</param>
//  /// <param name="xiansunlv">线损率字段</param>
//  /// <param name="tablehz">表后缀</param>
//  /// <returns>SQL语句</returns>
//  public  string SQL(DateTime starttime,DateTime endtime,string dw,float startxsl,float endxsl,string danwei,string xiansunlv,string tablehz)
//  {
//
//   string sql=null;
//   //将输入的时间格式转换成固定的格式"yyyy-mm-dd"
//   string zstarttime=starttime.GetDateTimeFormats('D')[1].ToString();
//   string zendtime=endtime.GetDateTimeFormats('D')[1].ToString();
//   string nTime=DateTime.Now.GetDateTimeFormats('D')[1].ToString();
//
//
//   //取日期值的前六位，及年月值
//   string sTime=zstarttime.Substring(0,4)+zstarttime.Substring(5,2);
//   string eTime=zendtime.Substring(0,4)+zendtime.Substring(5,2);
//   string nowTime=nTime.Substring(0,4)+nTime.Substring(5,2);
//   //分别取日期的年和月
//   int sy=Convert.ToInt32(zstarttime.Substring(0,4));
//   int ey=Convert.ToInt32(zendtime.Substring(0,4));
//   int sm=Convert.ToInt32(zstarttime.Substring(5,2));
//   int em=Convert.ToInt32(zendtime.Substring(5,2));
//   //相关变量定义
//   int s;
//   int e;
//   int i;
//   int j;
//   int js;
//   int nz;
//   string x;
//   //一，取当前表生成SQL语句
//   if(sTime==nowTime&&eTime==nowTime)
//   {
//    sql="select  * from "+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" ";
//   }
//    //二，取当前表和其他表生成SQL语句
//   else if(sTime==nowTime&&eTime!=nowTime)
//   {
//    sql="select  * from "+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//    //如果年份相等
//    if(sy==ey)
//    {
//     s=Convert.ToInt32(sTime);
//     e=Convert.ToInt32(eTime);
//     for(i=s+1;i<e;i++)
//     {
//      i=i++;
//      sql+="select  * from "+i.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//     }
//     sql+="select  * from "+e.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" ";
//    }
//     //结束年份大于开始年份
//    else
//    {
//     //1，先循环到起始时间和起始时间的12月
//     s=Convert.ToInt32(sTime);
//     x=zstarttime.Substring(0,4)+"12";
//     nz=Convert.ToInt32(x);
//     for(i=s+1;i<=nz;i++)
//     {
//      i=i++;
//      sql+="select  * from "+i.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//     }
//     //2，循环两者相差年份
//     for(i=sy+1;i<ey;i++)
//     {
//
//      for(j=1;j<=12;j++)
//      {
//       if(j<10)
//       {
//        sql+="select  * from "+i.ToString()+"0"+j.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//       }
//       else
//       {
//        sql+="select  * from "+i.ToString()+j.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//       }
//      }
//     }
//     //3，循环到结束的月份
//     js=Convert.ToInt32(zendtime.Substring(0,4)+"00");
//     for(i=js;i<Convert.ToInt32(eTime);i++)
//     {
//      i++;
//      sql+="select  * from "+i.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//
//     }
//     sql+="select  * from "+eTime.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" ";
//
//    }
//   }
//    //三，取其他表生成生成SQL语句
//   else
//   {
//    //1，先循环到起始时间和起始时间的12月
//    s=Convert.ToInt32(sTime);
//    x=zstarttime.Substring(0,4)+"12";
//    nz=Convert.ToInt32(x);
//    for(i=s;i<=nz;i++)
//    {
//     i=i++;
//     sql+="select  * from "+i.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//    }
//    //2，循环两者相差年份
//    for(i=sy+1;i<ey;i++)
//    {
//
//     for(j=1;j<=12;j++)
//     {
//      if(j<10)
//      {
//       sql+="select  * from "+i.ToString()+"0"+j.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//      }
//      else
//      {
//       sql+="select  * from "+i.ToString()+j.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//      }
//     }
//    }
//    //3，循环到结束的月份
//    js=Convert.ToInt32(zendtime.Substring(0,4)+"00");
//    for(i=js;i<Convert.ToInt32(eTime);i++)
//    {
//     i++;
//     sql+="select  * from "+i.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" "+"union"+" ";
//
//    }
//    sql+="select  * from "+eTime.ToString()+'_'+tablehz+" "+"where"+" "+danwei+"="+dw+" "+" "+"and"+" "+xiansunlv+">="+startxsl+" "+"and"+" "+xiansunlv+"<="+endxsl+" ";
//
//   }
//   return sql;
//  }
//  #endregion

//
//  #region 根据查询时间的条件，动态生成查询语句
//  /// <summary>
//  /// 根据查询时间的条件，动态生成查询语句
//  /// </summary>
//  /// <param name="starttime">开始时间</param>
//  /// <param name="endtime">结束时间</param>
//  /// <param name="zhiduan">查询字段</param>
//  /// <param name="tiaojiao">查询条件</param>
//  /// <param name="tablehz">表后缀</param>
//  /// <returns>SQL语句</returns>
//  public  string SQL(DateTime starttime,DateTime endtime,string zhiduan,string tiaojiao,string tablehz)
//  {
//
//   string sql=null;
//   //将输入的时间格式转换成固定的格式"yyyy-mm-dd"
//   string zstarttime=starttime.GetDateTimeFormats('D')[1].ToString();
//   string zendtime=endtime.GetDateTimeFormats('D')[1].ToString();
//   string nTime=DateTime.Now.GetDateTimeFormats('D')[1].ToString();
//
//
//   //取日期值的前六位，及年月值
//   string sTime=zstarttime.Substring(0,4)+zstarttime.Substring(5,2);
//   string eTime=zendtime.Substring(0,4)+zendtime.Substring(5,2);
//   string nowTime=nTime.Substring(0,4)+nTime.Substring(5,2);
//   //分别取日期的年和月
//   int sy=Convert.ToInt32(zstarttime.Substring(0,4));
//   int ey=Convert.ToInt32(zendtime.Substring(0,4));
//   int sm=Convert.ToInt32(zstarttime.Substring(5,2));
//   int em=Convert.ToInt32(zendtime.Substring(5,2));
//   //相关变量定义
//   int s;
//   int e;
//   int i;
//   int j;
//   int js;
//   int nz;
//   string x;
//   //一，取当前表生成SQL语句
//   if(sTime==nowTime&&eTime==nowTime)
//   {
//    sql="select"+" "+zhiduan+" "+"from"+" "+tablehz+" "+"where"+" "+tiaojiao+" ";
//
//   }
//    //二，取当前表和其他表生成SQL语句
//   else if(sTime==nowTime&&eTime!=nowTime)
//   {
//    sql="select"+" "+zhiduan+" "+"from"+" "+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//    //如果年份相等
//    if(sy==ey)
//    {
//     s=Convert.ToInt32(sTime);
//     e=Convert.ToInt32(eTime);
//     for(i=s+1;i<e;i++)
//     {
//      i=i++;
//      sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//     }
//     sql+="select"+" "+zhiduan+" "+"from"+" "+e.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" ";
//
//    }
//     //结束年份大于开始年份
//    else
//    {
//     //1，先循环到起始时间和起始时间的12月
//     s=Convert.ToInt32(sTime);
//     x=zstarttime.Substring(0,4)+"12";
//     nz=Convert.ToInt32(x);
//     for(i=s+1;i<=nz;i++)
//     {
//      i=i++;
//      sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//     }
//     //2，循环两者相差年份
//     for(i=sy+1;i<ey;i++)
//     {
//
//      for(j=1;j<=12;j++)
//      {
//       if(j<10)
//       {
//        sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+"0"+j.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//       }
//       else
//       {
//        sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+j.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//       }
//      }
//     }
//     //3，循环到结束的月份
//     js=Convert.ToInt32(zendtime.Substring(0,4)+"00");
//     for(i=js;i<Convert.ToInt32(eTime);i++)
//     {
//      i++;
//      sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//     }
//     sql+="select"+" "+zhiduan+" "+"from"+" "+eTime.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" ";
//
//    }
//   }
//    //三，取其他表生成生成SQL语句
//   else
//   {
//    //1，先循环到起始时间和起始时间的12月
//    s=Convert.ToInt32(sTime);
//    x=zstarttime.Substring(0,4)+"12";
//    nz=Convert.ToInt32(x);
//    for(i=s;i<=nz;i++)
//    {
//     i=i++;
//     sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//    }
//    //2，循环两者相差年份
//    for(i=sy+1;i<ey;i++)
//    {
//
//     for(j=1;j<=12;j++)
//     {
//      if(j<10)
//      {
//       sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+"0"+j.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//      }
//      else
//      {
//       sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+j.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//      }
//     }
//    }
//    //3，循环到结束的月份
//    js=Convert.ToInt32(zendtime.Substring(0,4)+"00");
//    for(i=js;i<Convert.ToInt32(eTime);i++)
//    {
//     i++;
//     sql+="select"+" "+zhiduan+" "+"from"+" "+i.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" "+"union"+" ";
//
//    }
//    sql+="select"+" "+zhiduan+" "+"from"+" "+eTime.ToString()+'_'+tablehz+" "+"where"+" "+tiaojiao+" ";
//
//   }
//   return sql;
//  }
//  #endregion

以下是另一个地址的

/***********************************************************************
 * Module:  OraHelper.cs
 * Author:  hellopj
 * Purpose: Definition of the Class OraHelper
 ***********************************************************************/ 

using System;
using System.Data;
using Oracle.DataAccess.Client;
using Oracle.DataAccess.Types;
using System.Collections;
using System.Configuration;
namespace OraHelper
{
 public abstract class OraHelper
 {
   public static readonly string CONN_STRING_NON_DTC = ConfigurationSettings.AppSettings["ConnStr"].Trim();
  public static OracleConnection conn = new OracleConnection(CONN_STRING_NON_DTC);

  public static void OpenConnection()
  {
   if (conn.State != ConnectionState.Open)
    conn.Open();
  }
  public static void CloseConnection()
  {
   if (conn.State == ConnectionState.Open)
    conn.Close();
  }
  public static DataSet getDataSet(string cmdText)
  {

   OracleDataAdapter Adapter = new OracleDataAdapter(cmdText,conn);
   DataSet Data = new DataSet();
   Adapter.Fill(Data);
   return Data;
  }
  public static OracleDataReader ExecuteReader(string cmdText)
  {

   OracleCommand cmd = new OracleCommand();
   cmd.Connection=conn;
   cmd.CommandText=cmdText;
   OracleDataReader rdr = cmd.ExecuteReader();
   cmd.Parameters.Clear();
   return rdr;
  }
  public static int ExecuteNonQuery(string cmdText)
  {
   try
   {
    OracleCommand comm=new OracleCommand(cmdText,conn);
    comm.ExecuteNonQuery();
    return ;
   }
   catch
   {
    return ;
   }
  }
  public static void ExecuteNonQuery(string cmdText,OracleConnection conn)
  {
   try
   {
    OracleCommand comm=new OracleCommand(cmdText,conn);
    comm.ExecuteNonQuery();
   }
   catch
   {

   }
  }
  public static string ExecuteScalar(string cmdText)
  {
   string status="";
   try
   {
    OracleCommand comm=new OracleCommand(cmdText,conn);
    status=comm.ExecuteScalar().ToString();
    return status;
   }
   catch(Exception err)
   {
    //return "-1";
    return err.Message.ToString();

   }
  }
  private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());
  public static int ExecuteNonQuery(CommandType cmdType, string cmdText, params OracleParameter[] cmdParms)
  {
   OracleCommand cmd = new OracleCommand();
   cmd.Connection = conn;
   cmd.Parameters.Clear();
   cmd.CommandText=cmdText;
   foreach (OracleParameter parm in cmdParms)
    cmd.Parameters.Add(parm);
   int val=cmd.ExecuteNonQuery();
   cmd.Parameters.Clear();
   return val;
  }

  public static int ExecuteNonQuery(OracleTransaction trans, CommandType cmdType, string cmdText, params OracleParameter[] cmdParms)
  {
   OracleCommand cmd = new OracleCommand();
   PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, cmdParms);
   int val = cmd.ExecuteNonQuery();
   cmd.Parameters.Clear();
   return val;
  }

  public static OracleDataReader ExecuteReader(CommandType cmdType, string cmdText, params OracleParameter[] cmdParms)
  {

   OracleCommand cmd = new OracleCommand();
   try
   {
    PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms);
    OracleDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
    cmd.Parameters.Clear();
    return rdr;

   }
   catch (Exception e)
   {
    conn.Close();
    throw e;
   }
  }

  public static object ExecuteScalar(string connString, CommandType cmdType, string cmdText, params OracleParameter[] cmdParms)
  {
   OracleCommand cmd = new OracleCommand();
   PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms);
   object val = cmd.ExecuteScalar();
   cmd.Parameters.Clear();
   return val;
  }

  public static object ExecuteScalar(CommandType cmdType, string cmdText, params OracleParameter[] cmdParms)
  {

   OracleCommand cmd = new OracleCommand();
   PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms);
   object val = cmd.ExecuteScalar();
   cmd.Parameters.Clear();
   return val;
  }

  public static int getScalar(CommandType cmdType, string cmdText, params OracleParameter[] cmdParms)
  {

   OracleCommand cmd = new OracleCommand();
   PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms);
   object val = cmd.ExecuteScalar();
   cmd.Parameters.Clear();
   int nVal  = Convert.ToInt32(val);
   return nVal;

  }

  public static void CacheParameters(string cacheKey, params OracleParameter[] cmdParms)
  {
   parmCache[cacheKey] = cmdParms;
  }

  public static OracleParameter[] GetCachedParameters(string cacheKey)
  {
   OracleParameter[] cachedParms = (OracleParameter[])parmCache[cacheKey];

   if (cachedParms == null)
    return null;

   OracleParameter[] clonedParms = new OracleParameter[cachedParms.Length];

   for (int i = , j = cachedParms.Length; i < j; i++)
    clonedParms[i] = (OracleParameter)((ICloneable)cachedParms[i]).Clone();

   return clonedParms;
  }

  private static void PrepareCommand(OracleCommand cmd, OracleConnection conn, OracleTransaction trans, CommandType cmdType, string cmdText, OracleParameter[] cmdParms)
  {

   if (conn.State != ConnectionState.Open)
    conn.Open();
   cmd.Connection = conn;
   cmd.CommandText = cmdText;
   cmd.CommandType = cmdType;
   //if (trans != null)
   //cmd.Transaction = trans;
   if (cmdParms != null)
   {
    foreach (OracleParameter parm in cmdParms)
     cmd.Parameters.Add(parm);
   }
  }

  public static int GetID(string SeqName) //得到序列的nextval
  {
   OracleCommand cmd = new OracleCommand();
   using (OracleConnection conn = new OracleConnection(CONN_STRING_NON_DTC))
   {
    string SqlText="select "+SeqName+".nextval from dual";

    PrepareCommand(cmd, conn, null, CommandType.Text,SqlText,null);
    int val = Convert.ToInt32(cmd.ExecuteScalar());
    cmd.Parameters.Clear();
    return val;
   }
  }
   }
}