【轉載】二位高手所寫的OleDb Help Class

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
using System.Data;
using System.Data.OleDb;
using System.Configuration;

namespace Athrun
{
    class OleDbDAL
    {
        //protected static string connectionString = ConfigurationSettings.AppSettings["DefaultDataSource"];//.net1.1
        protected static string connectionString = System.Configuration.ConfigurationManager.ConnectionStrings["connString"].ToString();
        public OleDbDAL()
        {
            //構造function
        }
        公用方法#region 公用方法

        public static int GetMaxID(string FieldName, string TableName)
        {
            string strsql = "select max(" + FieldName + ")+1 from " + TableName;
            object obj = GetSingle(strsql);
            if (obj == null)
            {
                return 1;
            }
            else
            {
                return int.Parse(obj.ToString());
            }
        }
        public static bool Exists(string strSql, params OleDbParameter[] cmdParms)
        {
            object obj = GetSingle(strSql, cmdParms);
            int cmdresult;
            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
            {
                cmdresult = 0;
            }
            else
            {
                cmdresult = int.Parse(obj.ToString());
            }
            if (cmdresult == 0)
            {
                return false;
            }
            else
            {
                return true;
            }
        }
        #endregion

        執行簡單SQL語句#region  執行簡單SQL語句

        /**//// <summary>
        /// 執行SQL語句，返回影響的記錄數
        /// </summary>
        /// <param name="SQLString">SQL語句</param>
        /// <returns>影響的記錄數</returns>
        public static int ExecuteSql(string SQLString)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                using (OleDbCommand cmd = new OleDbCommand(SQLString, connection))
                {
                    try
                    {
                        connection.Open();
                        int rows = cmd.ExecuteNonQuery();
                        return rows;
                    }
                    catch (System.Data.OleDb.OleDbException E)
                    {
                        connection.Close();
                        throw new Exception(E.Message);
                    }
                }
            }
        }

        /**//// <summary>
        /// 執行多條SQL語句，實現數據庫事務。
        /// </summary>
        /// <param name="SQLStringList">多條SQL語句</param>        
        public static void ExecuteSqlTran(ArrayList SQLStringList)
        {
            using (OleDbConnection conn = new OleDbConnection(connectionString))
            {
                conn.Open();
                OleDbCommand cmd = new OleDbCommand();
                cmd.Connection = conn;
                OleDbTransaction tx = conn.BeginTransaction();
                cmd.Transaction = tx;
                try
                {
                    for (int n = 0; n < SQLStringList.Count; n++)
                    {
                        string strsql = SQLStringList[n].ToString();
                        if (strsql.Trim().Length > 1)
                        {
                            cmd.CommandText = strsql;
                            cmd.ExecuteNonQuery();
                        }
                    }
                    tx.Commit();
                }
                catch (System.Data.OleDb.OleDbException E)
                {
                    tx.Rollback();
                    throw new Exception(E.Message);
                }
            }
        }
        /**//// <summary>
        /// 執行帶一個存儲過程參數的的SQL語句。
        /// </summary>
        /// <param name="SQLString">SQL語句</param>
        /// <param name="content">參數內容,比如一個字段是格式復雜的文章，有特殊符號，可以通過這個方式添加</param>
        /// <returns>影響的記錄數</returns>
        public static int ExecuteSql(string SQLString, string content)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                OleDbCommand cmd = new OleDbCommand(SQLString, connection);
                System.Data.OleDb.OleDbParameter myParameter = new System.Data.OleDb.OleDbParameter("@content", OleDbType.VarChar);
                myParameter.Value = content;
                cmd.Parameters.Add(myParameter);
                try
                {
                    connection.Open();
                    int rows = cmd.ExecuteNonQuery();
                    return rows;
                }
                catch (System.Data.OleDb.OleDbException E)
                {
                    throw new Exception(E.Message);
                }
                finally
                {
                    cmd.Dispose();
                    connection.Close();
                }
            }
        }
        /**//// <summary>
        /// 向數據庫裡插入圖像格式的字段(和上面情況類似的另一種實例)
        /// </summary>
        /// <param name="strSQL">SQL語句</param>
        /// <param name="fs">圖像字節,數據庫的字段類型為image的情況</param>
        /// <returns>影響的記錄數</returns>
        public static int ExecuteSqlInsertImg(string strSQL, byte[] fs)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                OleDbCommand cmd = new OleDbCommand(strSQL, connection);
                System.Data.OleDb.OleDbParameter myParameter = new System.Data.OleDb.OleDbParameter("@fs", OleDbType.Binary);
                myParameter.Value = fs;
                cmd.Parameters.Add(myParameter);
                try
                {
                    connection.Open();
                    int rows = cmd.ExecuteNonQuery();
                    return rows;
                }
                catch (System.Data.OleDb.OleDbException E)
                {
                    throw new Exception(E.Message);
                }
                finally
                {
                    cmd.Dispose();
                    connection.Close();
                }
            }
        }

        /**//// <summary>
        /// 執行一條計算查詢結果語句，返回查詢結果（object）。
        /// </summary>
        /// <param name="SQLString">計算查詢結果語句</param>
        /// <returns>查詢結果（object）</returns>
        public static object GetSingle(string SQLString)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                using (OleDbCommand cmd = new OleDbCommand(SQLString, connection))
                {
                    try
                    {
                        connection.Open();
                        object obj = cmd.ExecuteScalar();
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                        {
                            return null;
                        }
                        else
                        {
                            return obj;
                        }
                    }
                    catch (System.Data.OleDb.OleDbException e)
                    {
                        connection.Close();
                        throw new Exception(e.Message);
                    }
                }
            }
        }
        /**//// <summary>
        /// 執行查詢語句，返回OleDbDataReader
        /// </summary>
        /// <param name="strSQL">查詢語句</param>
        /// <returns>OleDbDataReader</returns>
        public static OleDbDataReader ExecuteReader(string strSQL)
        {
            OleDbConnection connection = new OleDbConnection(connectionString);
            OleDbCommand cmd = new OleDbCommand(strSQL, connection);
            try
            {
                connection.Open();
                OleDbDataReader myReader = cmd.ExecuteReader();
                return myReader;
            }
            catch (System.Data.OleDb.OleDbException e)
            {
                throw new Exception(e.Message);
            }

        }
        /**//// <summary>
        /// 執行查詢語句，返回DataSet
        /// </summary>
        /// <param name="SQLString">查詢語句</param>
        /// <returns>DataSet</returns>
        public static DataSet Query(string SQLString)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                DataSet ds = new DataSet();
                try
                {
                    connection.Open();
                    OleDbDataAdapter command = new OleDbDataAdapter(SQLString, connection);
                    command.Fill(ds, "ds");
                }
                catch (System.Data.OleDb.OleDbException ex)
                {
                    throw new Exception(ex.Message);
                }
                return ds;
            }
        }


        #endregion

        執行帶參數的SQL語句#region 執行帶參數的SQL語句

        /**//// <summary>
        /// 執行SQL語句，返回影響的記錄數
        /// </summary>
        /// <param name="SQLString">SQL語句</param>
        /// <returns>影響的記錄數</returns>
        public static int ExecuteSql(string SQLString, params OleDbParameter[] cmdParms)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                using (OleDbCommand cmd = new OleDbCommand())
                {
                    try
                    {
                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                        int rows = cmd.ExecuteNonQuery();
                        cmd.Parameters.Clear();
                        return rows;
                    }
                    catch (System.Data.OleDb.OleDbException E)
                    {
                        throw new Exception(E.Message);
                    }
                }
            }
        }


        /**//// <summary>
        /// 執行多條SQL語句，實現數據庫事務。
        /// </summary>
        /// <param name="SQLStringList">SQL語句的哈希表（key為sql語句，value是該語句的OleDbParameter[]）</param>
        public static void ExecuteSqlTran(Hashtable SQLStringList)
        {
            using (OleDbConnection conn = new OleDbConnection(connectionString))
            {
                conn.Open();
                using (OleDbTransaction trans = conn.BeginTransaction())
                {
                    OleDbCommand cmd = new OleDbCommand();
                    try
                    {
                        //循環
                        foreach (DictionaryEntry myDE in SQLStringList)
                        {
                            string cmdText = myDE.Key.ToString();
                            OleDbParameter[] cmdParms = (OleDbParameter[])myDE.Value;
                            PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                            int val = cmd.ExecuteNonQuery();
                            cmd.Parameters.Clear();

                            trans.Commit();
                        }
                    }
                    catch
                    {
                        trans.Rollback();
                        throw;
                    }
                }
            }
        }


        /**//// <summary>
        /// 執行一條計算查詢結果語句，返回查詢結果（object）。
        /// </summary>
        /// <param name="SQLString">計算查詢結果語句</param>
        /// <returns>查詢結果（object）</returns>
        public static object GetSingle(string SQLString, params OleDbParameter[] cmdParms)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                using (OleDbCommand cmd = new OleDbCommand())
                {
                    try
                    {
                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                        object obj = cmd.ExecuteScalar();
                        cmd.Parameters.Clear();
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                        {
                            return null;
                        }
                        else
                        {
                            return obj;
                        }
                    }
                    catch (System.Data.OleDb.OleDbException e)
                    {
                        throw new Exception(e.Message);
                    }
                }
            }
        }

        /**//// <summary>
        /// 執行查詢語句，返回OleDbDataReader
        /// </summary>
        /// <param name="strSQL">查詢語句</param>
        /// <returns>OleDbDataReader</returns>
        public static OleDbDataReader ExecuteReader(string SQLString, params OleDbParameter[] cmdParms)
        {
            OleDbConnection connection = new OleDbConnection(connectionString);
            OleDbCommand cmd = new OleDbCommand();
            try
            {
                PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                OleDbDataReader myReader = cmd.ExecuteReader();
                cmd.Parameters.Clear();
                return myReader;
            }
            catch (System.Data.OleDb.OleDbException e)
            {
                throw new Exception(e.Message);
            }

        }

        /**//// <summary>
        /// 執行查詢語句，返回DataSet
        /// </summary>
        /// <param name="SQLString">查詢語句</param>
        /// <returns>DataSet</returns>
        public static DataSet Query(string SQLString, params OleDbParameter[] cmdParms)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                OleDbCommand cmd = new OleDbCommand();
                PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                using (OleDbDataAdapter da = new OleDbDataAdapter(cmd))
                {
                    DataSet ds = new DataSet();
                    try
                    {
                        da.Fill(ds, "ds");
                        cmd.Parameters.Clear();
                    }
                    catch (System.Data.OleDb.OleDbException ex)
                    {
                        throw new Exception(ex.Message);
                    }
                    return ds;
                }
            }
        }


        private static void PrepareCommand(OleDbCommand cmd, OleDbConnection conn, OleDbTransaction trans, string cmdText, OleDbParameter[] cmdParms)
        {
            if (conn.State != ConnectionState.Open)
                conn.Open();
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            if (trans != null)
                cmd.Transaction = trans;
            cmd.CommandType = CommandType.Text;//cmdType;
            if (cmdParms != null)
            {
                foreach (OleDbParameter parm in cmdParms)
                    cmd.Parameters.Add(parm);
            }
        }

        #endregion

        存儲過程操作#region 存儲過程操作

        /**//// <summary>
        /// 執行存儲過程
        /// </summary>
        /// <param name="storedProcName">存儲過程名</param>
        /// <param name="parameters">存儲過程參數</param>
        /// <returns>OleDbDataReader</returns>
        public static OleDbDataReader RunProcedure(string storedProcName, IDataParameter[] parameters)
        {
            OleDbConnection connection = new OleDbConnection(connectionString);
            OleDbDataReader returnReader;
            connection.Open();
            OleDbCommand command = BuildQueryCommand(connection, storedProcName, parameters);
            command.CommandType = CommandType.StoredProcedure;
            returnReader = command.ExecuteReader();
            return returnReader;
        }


        /**//// <summary>
        /// 執行存儲過程
        /// </summary>
        /// <param name="storedProcName">存儲過程名</param>
        /// <param name="parameters">存儲過程參數</param>
        /// <param name="tableName">DataSet結果中的表名</param>
        /// <returns>DataSet</returns>
        public static DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                DataSet dataSet = new DataSet();
                connection.Open();
                OleDbDataAdapter sqlDA = new OleDbDataAdapter();
                sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters);
                sqlDA.Fill(dataSet, tableName);
                connection.Close();
                return dataSet;
            }
        }


        /**//// <summary>
        /// 構建 OleDbCommand 對像(用來返回一個結果集，而不是一個整數值)
        /// </summary>
        /// <param name="connection">數據庫連接</param>
        /// <param name="storedProcName">存儲過程名</param>
        /// <param name="parameters">存儲過程參數</param>
        /// <returns>OleDbCommand</returns>
        private static OleDbCommand BuildQueryCommand(OleDbConnection connection, string storedProcName, IDataParameter[] parameters)
        {
            OleDbCommand command = new OleDbCommand(storedProcName, connection);
            command.CommandType = CommandType.StoredProcedure;
            foreach (OleDbParameter parameter in parameters)
            {
                command.Parameters.Add(parameter);
            }
            return command;
        }

        /**//// <summary>
        /// 執行存儲過程，返回影響的行數        
        /// </summary>
        /// <param name="storedProcName">存儲過程名</param>
        /// <param name="parameters">存儲過程參數</param>
        /// <param name="rowsAffected">影響的行數</param>
        /// <returns></returns>
        public static int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected)
        {
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                int result;
                connection.Open();
                OleDbCommand command = BuildIntCommand(connection, storedProcName, parameters);
                rowsAffected = command.ExecuteNonQuery();
                result = (int)command.Parameters["ReturnValue"].Value;
                //Connection.Close();
                return result;
            }
        }

        /**//// <summary>
        /// 創建 OleDbCommand 對像實例(用來返回一個整數值)    
        /// </summary>
        /// <param name="storedProcName">存儲過程名</param>
        /// <param name="parameters">存儲過程參數</param>
        /// <returns>OleDbCommand 對像實例</returns>
        private static OleDbCommand BuildIntCommand(OleDbConnection connection, string storedProcName, IDataParameter[] parameters)
        {
            OleDbCommand command = BuildQueryCommand(connection, storedProcName, parameters);
            command.Parameters.Add(new OleDbParameter("ReturnValue",
                OleDbType.Integer, 4, ParameterDirection.ReturnValue,
                false, 0, 0, string.Empty, DataRowVersion.Default, null));
            return command;
        }
        #endregion    
    }
}

1

 using System;
 using System.Collections;
 using System.Collections.Specialized;
 using System.Data;
 using System.Data.OleDb;
 using System.Configuration;
 
   
     public  class DBHelper
     {
         //数据库连接字符串(web.config来配置)
         //<add key="ConnectionString" value="server=127.0.0.1;database=DATABASE;uid=sa;pwd=" />        
         protected static string connectionString = ConfigurationSettings.AppSettings["ConnectionString"];
      
 
         执行简单SQL语句#region  执行简单SQL语句
 
         /**//// <summary>
         /// 执行SQL语句，返回影响的记录数
         /// </summary>
         /// <param name="SQLString">SQL语句</param>
         /// <returns>影响的记录数</returns>
         public static int ExecuteSql(string SQLString)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 using (OleDbCommand cmd = new OleDbCommand(SQLString, connection))
                 {
                     try
                     {
                         connection.Open();
                         int rows = cmd.ExecuteNonQuery();
                         return rows;
                     }
                     catch (System.Data.OleDb.OleDbException E)
                     {
                         connection.Close();
                         throw new Exception(E.Message);
                     }
                 }
             }
         }
 
         /**//// <summary>
         /// 执行多条SQL语句，实现数据库事务。
         /// </summary>
         /// <param name="SQLStringList">多条SQL语句</param>        
         public static void ExecuteSqlTran(ArrayList SQLStringList)
         {
             using (OleDbConnection conn = new OleDbConnection(connectionString))
             {
                 conn.Open();
                 OleDbCommand cmd = new OleDbCommand();
                 cmd.Connection = conn;
                 OleDbTransaction tx = conn.BeginTransaction();
                 cmd.Transaction = tx;
                 try
                 {
                     for (int n = 0; n < SQLStringList.Count; n++)
                     {
                         string strsql = SQLStringList[n].ToString();
                         if (strsql.Trim().Length > 1)
                         {
                             cmd.CommandText = strsql;
                             cmd.ExecuteNonQuery();
                         }
                     }
                     tx.Commit();
                 }
                 catch (System.Data.OleDb.OleDbException E)
                 {
                     tx.Rollback();
                     throw new Exception(E.Message);
                 }
             }
         }
         /**//// <summary>
         /// 执行带一个存储过程参数的的SQL语句。
         /// </summary>
         /// <param name="SQLString">SQL语句</param>
         /// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加</param>
         /// <returns>影响的记录数</returns>
         public static int ExecuteSql(string SQLString, string content)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 OleDbCommand cmd = new OleDbCommand(SQLString, connection);
                 System.Data.OleDb.OleDbParameter myParameter = new System.Data.OleDb.OleDbParameter("@content", 
 
 OleDbType.VarChar);
                 myParameter.Value = content;
                 cmd.Parameters.Add(myParameter);
                 try
                 {
                     connection.Open();
                     int rows = cmd.ExecuteNonQuery();
                     return rows;
                 }
                 catch (System.Data.OleDb.OleDbException E)
                 {
                     throw new Exception(E.Message);
                 }
                 finally
                 {
                     cmd.Dispose();
                     connection.Close();
                 }
             }
         }
         /**//// <summary>
         /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例)
         /// </summary>
         /// <param name="strSQL">SQL语句</param>
         /// <param name="fs">图像字节,数据库的字段类型为image的情况</param>
         /// <returns>影响的记录数</returns>
         public static int ExecuteSqlInsertImg(string strSQL, byte[] fs)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 OleDbCommand cmd = new OleDbCommand(strSQL, connection);
                 System.Data.OleDb.OleDbParameter myParameter = new System.Data.OleDb.OleDbParameter("@fs", OleDbType.Binary);
                 myParameter.Value = fs;
                 cmd.Parameters.Add(myParameter);
                 try
                 {
                     connection.Open();
                     int rows = cmd.ExecuteNonQuery();
                     return rows;
                 }
                 catch (System.Data.OleDb.OleDbException E)
                 {
                     throw new Exception(E.Message);
                 }
                 finally
                 {
                     cmd.Dispose();
                     connection.Close();
                 }
             }
         }
 
         /**//// <summary>
         /// 执行一条计算查询结果语句，返回查询结果（object）。
         /// </summary>
         /// <param name="SQLString">计算查询结果语句</param>
         /// <returns>查询结果（object）</returns>
         public static object GetSingle(string SQLString)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 using (OleDbCommand cmd = new OleDbCommand(SQLString, connection))
                 {
                     try
                     {
                         connection.Open();
                         object obj = cmd.ExecuteScalar();
                         if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                         {
                             return null;
                         }
                         else
                         {
                             return obj;
                         }
                     }
                     catch (System.Data.OleDb.OleDbException e)
                     {
                         connection.Close();
                         throw new Exception(e.Message);
                     }
                 }
             }
         }
         /**//// <summary>
         /// 执行查询语句，返回OleDbDataReader
         /// </summary>
         /// <param name="strSQL">查询语句</param>
         /// <returns>OleDbDataReader</returns>
         public static OleDbDataReader ExecuteReader(string strSQL)
         {
             OleDbConnection connection = new OleDbConnection(connectionString);
             OleDbCommand cmd = new OleDbCommand(strSQL, connection);
             try
             {
                 connection.Open();
                 OleDbDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                 return myReader;
             }
             catch (System.Data.OleDb.OleDbException e)
             {
                 throw new Exception(e.Message);
             }
 
         }
         /**//// <summary>
         /// 执行查询语句，返回DataSet
         /// </summary>
         /// <param name="SQLString">查询语句</param>
         /// <returns>DataSet</returns>
         public static DataSet Query(string SQLString)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 DataSet ds = new DataSet();
                 try
                 {
                     connection.Open();
                     OleDbDataAdapter command = new OleDbDataAdapter(SQLString, connection);
                     command.Fill(ds, "ds");
                 }
                 catch (System.Data.OleDb.OleDbException ex)
                 {
                     throw new Exception(ex.Message);
                 }
                 return ds;
             }
         }
 
 
         #endregion
 
         执行带参数的SQL语句#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="SQLString">SQL语句</param>
         /// <returns>影响的记录数</returns>
         public static int ExecuteSql(string SQLString, params OleDbParameter[] cmdParms)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 using (OleDbCommand cmd = new OleDbCommand())
                 {
                     try
                     {
                         PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                         int rows = cmd.ExecuteNonQuery();
                         cmd.Parameters.Clear();
                         return rows;
                     }
                     catch (System.Data.OleDb.OleDbException E)
                     {
                         throw new Exception(E.Message);
                     }
                 }
             }
         }
 
 
         /**//// <summary>
         /// 执行多条SQL语句，实现数据库事务。
         /// </summary>
         /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的OleDbParameter[]）</param>
         public static void ExecuteSqlTran(Hashtable SQLStringList)
         {
             using (OleDbConnection conn = new OleDbConnection(connectionString))
             {
                 conn.Open();
                 using (OleDbTransaction trans = conn.BeginTransaction())
                 {
                     OleDbCommand cmd = new OleDbCommand();
                     try
                     {
                         //循环
                         foreach (DictionaryEntry myDE in SQLStringList)
                         {
                             string cmdText = myDE.Key.ToString();
                             OleDbParameter[] cmdParms = (OleDbParameter[])myDE.Value;
                             PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                             int val = cmd.ExecuteNonQuery();
                             cmd.Parameters.Clear();
                             trans.Commit();
                         }
                     }
                     catch
                     {
                         trans.Rollback();
                         throw;
                     }
                 }
             }
         }
 
 
         /**//// <summary>
         /// 执行一条计算查询结果语句，返回查询结果（object）。
         /// </summary>
         /// <param name="SQLString">计算查询结果语句</param>
         /// <returns>查询结果（object）</returns>
         public static object GetSingle(string SQLString, params OleDbParameter[] cmdParms)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 using (OleDbCommand cmd = new OleDbCommand())
                 {
                     try
                     {
                         PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                         object obj = cmd.ExecuteScalar();
                         cmd.Parameters.Clear();
                         if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                         {
                             return null;
                         }
                         else
                         {
                             return obj;
                         }
                     }
                     catch (System.Data.OleDb.OleDbException e)
                     {
                         throw new Exception(e.Message);
                     }
                 }
             }
         }
 
         /**//// <summary>
         /// 执行查询语句，返回OleDbDataReader
         /// </summary>
         /// <param name="strSQL">查询语句</param>
         /// <returns>OleDbDataReader</returns>
         public static OleDbDataReader ExecuteReader(string SQLString, params OleDbParameter[] cmdParms)
         {
             OleDbConnection connection = new OleDbConnection(connectionString);
             OleDbCommand cmd = new OleDbCommand();
             try
             {
                 PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                 OleDbDataReader myReader = cmd.ExecuteReader();
                 cmd.Parameters.Clear();
                 return myReader;
             }
             catch (System.Data.OleDb.OleDbException e)
             {
                 throw new Exception(e.Message);
             }
 
         }
 
         /**//// <summary>
         /// 执行查询语句，返回DataSet
         /// </summary>
         /// <param name="SQLString">查询语句</param>
         /// <returns>DataSet</returns>
         public static DataSet Query(string SQLString, params OleDbParameter[] cmdParms)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 OleDbCommand cmd = new OleDbCommand();
                 PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                 using (OleDbDataAdapter da = new OleDbDataAdapter(cmd))
                 {
                     DataSet ds = new DataSet();
                     try
                     {
                         da.Fill(ds, "ds");
                         cmd.Parameters.Clear();
                     }
                     catch (System.Data.OleDb.OleDbException ex)
                     {
                         throw new Exception(ex.Message);
                     }
                     return ds;
                 }
             }
         }
 
 
         private static void PrepareCommand(OleDbCommand cmd, OleDbConnection conn, OleDbTransaction trans, string cmdText, 
 
 OleDbParameter[] cmdParms)
         {
             if (conn.State != ConnectionState.Open)
                 conn.Open();
             cmd.Connection = conn;
             cmd.CommandText = cmdText;
             if (trans != null)
                 cmd.Transaction = trans;
             cmd.CommandType = CommandType.Text;//cmdType;
             if (cmdParms != null)
             {
                 foreach (OleDbParameter parm in cmdParms)
                     cmd.Parameters.Add(parm);
             }
         }
 
         #endregion
 
         存储过程操作#region 存储过程操作
 
         /**//// <summary>
         /// 执行存储过程
         /// </summary>
         /// <param name="storedProcName">存储过程名</param>
         /// <param name="parameters">存储过程参数</param>
         /// <returns>OleDbDataReader</returns>
         public static OleDbDataReader RunProcedure(string storedProcName, IDataParameter[] parameters)
         {
             OleDbConnection connection = new OleDbConnection(connectionString);
             OleDbDataReader returnReader;
             connection.Open();
             OleDbCommand command = BuildQueryCommand(connection, storedProcName, parameters);
             command.CommandType = CommandType.StoredProcedure;
             returnReader = command.ExecuteReader();
             return returnReader;
         }
 
 
         /**//// <summary>
         /// 执行存储过程
         /// </summary>
         /// <param name="storedProcName">存储过程名</param>
         /// <param name="parameters">存储过程参数</param>
         /// <param name="tableName">DataSet结果中的表名</param>
         /// <returns>DataSet</returns>
         public static DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 DataSet dataSet = new DataSet();
                 connection.Open();
                 OleDbDataAdapter sqlDA = new OleDbDataAdapter();
                 sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters);
                 sqlDA.Fill(dataSet, tableName);
                 connection.Close();
                 return dataSet;
             }
         }
 
 
         /**//// <summary>
         /// 构建 OleDbCommand 对象(用来返回一个结果集，而不是一个整数值)
         /// </summary>
         /// <param name="connection">数据库连接</param>
         /// <param name="storedProcName">存储过程名</param>
         /// <param name="parameters">存储过程参数</param>
         /// <returns>OleDbCommand</returns>
         private static OleDbCommand BuildQueryCommand(OleDbConnection connection, string storedProcName, IDataParameter[] 
 
 parameters)
         {
             OleDbCommand command = new OleDbCommand(storedProcName, connection);
             command.CommandType = CommandType.StoredProcedure;
             foreach (OleDbParameter parameter in parameters)
             {
                 command.Parameters.Add(parameter);
             }
             return command;
         }
 
         /**//// <summary>
         /// 执行存储过程，返回影响的行数        
         /// </summary>
         /// <param name="storedProcName">存储过程名</param>
         /// <param name="parameters">存储过程参数</param>
         /// <param name="rowsAffected">影响的行数</param>
         /// <returns></returns>
         public static int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected)
         {
             using (OleDbConnection connection = new OleDbConnection(connectionString))
             {
                 int result;
                 connection.Open();
                 OleDbCommand command = BuildIntCommand(connection, storedProcName, parameters);
                 rowsAffected = command.ExecuteNonQuery();
                 result = (int)command.Parameters["ReturnValue"].Value;
                 //Connection.Close();
                 return result;
             }
         }
 
         /**//// <summary>
         /// 创建 OleDbCommand 对象实例(用来返回一个整数值)    
         /// </summary>
         /// <param name="storedProcName">存储过程名</param>
         /// <param name="parameters">存储过程参数</param>
         /// <returns>OleDbCommand 对象实例</returns>
         private static OleDbCommand BuildIntCommand(OleDbConnection connection, string storedProcName, IDataParameter[] 
 
 parameters)
         {
             OleDbCommand command = BuildQueryCommand(connection, storedProcName, parameters);
             command.Parameters.Add(new OleDbParameter("ReturnValue",
                 OleDbType.Integer, 4, ParameterDirection.ReturnValue,
                 false, 0, 0, string.Empty, DataRowVersion.Default, null));
             return command;
         }
         #endregion
 
     }