using System;using System.Text;using System.Collections;using System.Collections.Specialized;using System.Data;using System.Data.OleDb;using System.Configuration;namespace HoverTree.Web.DBUtility{  /// <summary>  /// 數據訪問抽象基礎類(ACCESS)  /// Copyright (C) 2006-2007 hovertree.net  /// All rights reserved  /// </summary>  public abstract class DbHelperACE  {    //數據庫連接字符串(web.config來配置)    //public static string connectionString = ConfigurationManager.AppSettings["ConnectionString"];    // public static string connectionString = System.Web.HttpContext.Current.Server.MapPath(ConfigurationManager.AppSettings["AccessConnectionString"]);    public static string connectionString = ConfigurationManager.AppSettings["AccessConnectionString"];    public DbHelperACE()    {    }    #region 公用方法    public static int GetMaxID(string FieldName, string TableName)    {      string strsql = "select max(" + FieldName + ")+1 from " + TableName;      object obj = DbHelperACE.GetSingle(strsql);      if (obj == null)      {        return 1;      }      else      {        return int.Parse(obj.ToString());      }    }    public static bool Exists(string strSql)    {      object obj = DbHelperACE.GetSingle(strSql);      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;      }    }    public static bool Exists(string strSql, params OleDbParameter[] cmdParms)    {      object obj = DbHelperACE.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    #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SQL語句，設置命令的執行等待時間    /// </summary>    /// <param name="SQLString"></param>    /// <param name="Times"></param>    /// <returns></returns>    public static int ExecuteSqlByTime(string SQLString, int Times)    {      using (OleDbConnection connection = new OleDbConnection(connectionString))      {        using (OleDbCommand cmd = new OleDbCommand(SQLString, connection))        {          try          {            connection.Open();            cmd.CommandTimeout = Times;            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>    /// 向數據庫里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", SqlDbType.Image);        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SqlDataReader(使用該方法切記要手工關閉SqlDataReader和連接)    /// </summary>    /// <param name="strSQL">查詢語句</param>    /// <returns>SqlDataReader</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);      }      //finally //不能在此關閉，否則，返回的對象將無法使用      //{      // cmd.Dispose();      // connection.Close();      //}    }    /// <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;      }    }    /// <summary>    /// 執行查詢語句，返回DataSet,設置命令的執行等待時間    /// </summary>    /// <param name="SQLString"></param>    /// <param name="Times"></param>    /// <returns></returns>    public static DataSet Query(string SQLString, int Times)    {      using (OleDbConnection connection = new OleDbConnection(connectionString))      {        DataSet ds = new DataSet();        try        {          connection.Open();          OleDbDataAdapter command = new OleDbDataAdapter(SQLString, connection);          command.SelectCommand.CommandTimeout = Times;          command.Fill(ds, "ds");        }        catch (System.Data.OleDb.OleDbException ex)        {          throw new Exception(ex.Message);        }        return ds;      }    }    #endregion    #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SqlDataReader (使用該方法切記要手工關閉SqlDataReader和連接)    /// </summary>    /// <param name="strSQL">查詢語句</param>    /// <returns>SqlDataReader</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);      }      //finally //不能在此關閉，否則，返回的對象將無法使用      //{      // cmd.Dispose();      // connection.Close();      //}    }    /// <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 parameter in cmdParms)        {          if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&            (parameter.Value == null))          {            parameter.Value = DBNull.Value;          }          cmd.Parameters.Add(parameter);        }      }    }    #endregion    #region 獲取根據指定字段排序并分頁查詢。        /// <summary>    /// 分頁查詢數據記錄總數獲取    /// </summary>    /// <param name="_tbName">----要顯示的表或多個表的連接</param>    /// <param name="_ID">----主表的主鍵</param>    /// <param name="_strCondition">----查詢條件,不需where</param>    /// <param name="_Dist">----是否添加查詢字段的 DISTINCT 默認0不添加/1添加</param>    /// <returns></returns>    public static string getPageListCounts(string _ID, string _tbName, string _strCondition, int _Dist)    {      //---存放取得查詢結果總數的查詢語句      //---對含有DISTINCT的查詢進行SQL構造      //---對含有DISTINCT的總數查詢進行SQL構造      string strTmp = "", SqlSelect = "", SqlCounts = "";      if (_Dist == 0)      {        SqlSelect = "Select ";        SqlCounts = "COUNT(*)";      }      else      {        SqlSelect = "Select DISTINCT ";        SqlCounts = "COUNT(DISTINCT " + _ID + ")";      }      if (_strCondition == string.Empty)      {        strTmp = SqlSelect + " "+ SqlCounts + " FROM " + _tbName;      }      else      {        strTmp = SqlSelect + " "+ SqlCounts + " FROM " + " Where (1=1) " + _strCondition;      }      return strTmp;    }    /// <summary>    /// 智能返回SQL語句    /// </summary>    /// <param name="primaryKey">主鍵（不能為空）</param>    /// <param name="queryFields">提取字段（不能為空）</param>    /// <param name="tableName">表（理論上允許多表）</param>    /// <param name="condition">條件（可以空）</param>    /// <param name="OrderBy">排序，格式：字段名+""+ASC（可以空）</param>    /// <param name="pageSize">分頁數（不能為空）</param>    /// <param name="pageIndex">當前頁，起始為：1（不能為空）</param>    /// <returns></returns>    public static string getPageListSql(string primaryKey, string queryFields, string tableName, string condition, string orderBy, int pageSize, int pageIndex)    {      string strTmp = ""; //---strTmp用于返回的SQL語句      string SqlSelect = "", SqlPrimaryKeySelect = "", strOrderBy = "", strWhere = " where 1=1 ", strTop = "";      //0：分頁數量      //1:提取字段      //2:表      //3:條件      //4:主鍵不存在的記錄      //5:排序      SqlSelect = " select top {0} {1} from {2} {3} {4} {5}";      //0:主鍵      //1:TOP數量,為分頁數*(排序號-1)      //2:表      //3:條件      //4:排序      SqlPrimaryKeySelect = " and {0} not in (select {1} {0} from {2} {3} {4}) ";      if (orderBy != "")        strOrderBy = " order by " + orderBy;      if (condition != "")        strWhere += " and " + condition;      int pageindexsize = (pageIndex - 1) * pageSize;      if (pageindexsize > 0)      {        strTop = " top " + pageindexsize.ToString();        SqlPrimaryKeySelect = String.Format(SqlPrimaryKeySelect, primaryKey, strTop, tableName, strWhere, strOrderBy);        strTmp = String.Format(SqlSelect, pageSize.ToString(), queryFields, tableName, strWhere, SqlPrimaryKeySelect, strOrderBy);      }      else      {        strTmp = String.Format(SqlSelect, pageSize.ToString(), queryFields, tableName, strWhere, "", strOrderBy);      }      return strTmp;    }    /// <summary>    /// 獲取根據指定字段排序并分頁查詢。DataSet    /// </summary>    /// <param name="pageSize">每頁要顯示的記錄的數目</param>    /// <param name="pageIndex">要顯示的頁的索引</param>    /// <param name="tableName">要查詢的數據表</param>    /// <param name="queryFields">要查詢的字段,如果是全部字段請填寫：*</param>    /// <param name="primaryKey">主鍵字段，類似排序用到</param>    /// <param name="orderBy">是否為升序排列：0為升序，1為降序</param>    /// <param name="condition">查詢的篩選條件</param>    /// <returns>返回排序并分頁查詢的DataSet</returns>    public static DataSet GetPagingList(string primaryKey, string queryFields, string tableName, string condition, string orderBy, int pageSize, int pageIndex)    {      string sql = getPageListSql(primaryKey, queryFields, tableName, condition, orderBy, pageSize, pageIndex);      return Query(sql);    }    public static string GetPagingListSQL(string primaryKey, string queryFields, string tableName, string condition, string orderBy, int pageSize, int pageIndex)    {      string sql = getPageListSql(primaryKey, queryFields, tableName, condition, orderBy, pageSize, pageIndex);      return sql;    }    public static int GetRecordCount(string _ID, string _tbName, string _strCondition, int _Dist)    {      string sql = getPageListCounts( _ID, _tbName, _strCondition, _Dist);      object obj = DbHelperACE.GetSingle(sql);      if (obj == null)      {        return 1;      }      else      {        return int.Parse(obj.ToString());      }    }    #endregion  }}