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本文实例讲述了C#实现Access通用访问类OleDbHelper。分享给大家供大家参考，具体如下：
最近在做一个项目数据库用的是Access,第一次使用Access数据库，刚开始做有些不顺，数据库的操作和SqlServer稍有些不同，而异常跟踪得到的信息也没有什么意义，经过几天的反复寻找问题，总算解决了一些问题，为了访问Access 数据库，我写了一个用于专门访问的类来操作数据库，其中包括，执行数据库命令，返回 DataSet，返回单条记录，返回DataReader，通用分页方法等几个常用的的操作方法。请各位提出意见，以便我完善这个类。虽是参考SqlHelper 但是比其简单的多，所有的代码如下：
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.Common;
using System.Data.OleDb;
namespace Common
{
/// <summary>
/// OleDb 书库访问类
/// </summary>
public static class OleDbHelper
{
/// <summary>
/// Access 的数据库连接字符串格式.
/// </summary>
public const string ACCESS_CONNECTIONSTRING_TEMPLATE = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};";
// Hashtable to store cached parameters
private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());
/// <summary>
/// 针对 System.Data.OleDb.OleDbCommand.Connection 执行 SQL 语句并返回受影响的行数.
/// </summary>
/// <param name="connString"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static int ExecuteNonQuery(string connString, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
using (OleDbConnection conn = new OleDbConnection(connString))
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms, ConnectionActionType.Open);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
}
/// <summary>
/// 针对 System.Data.OleDb.OleDbCommand.Connection 执行 SQL 语句并返回受影响的行数.
/// </summary>
/// <param name="conn"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static int ExecuteNonQuery(OleDbConnection conn, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms, ConnectionActionType.AutoDetection);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
/// <summary>
/// 针对 System.Data.OleDb.OleDbCommand.Connection 执行 SQL 语句并返回受影响的行数.
/// </summary>
/// <param name="trans"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static int ExecuteNonQuery(OleDbTransaction trans, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, cmdParms, ConnectionActionType.None);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
/// <summary>
/// 将 System.Data.OleDb.OleDbCommand.CommandText 发送到 System.Data.OleDb.OleDbCommand.Connection 并生成一个 System.Data.OleDb.OleDbDataReader.
/// </summary>
/// <param name="connString"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static OleDbDataReader ExecuteReader(string connString, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
OleDbConnection conn = new OleDbConnection(connString);
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms, ConnectionActionType.Open);
OleDbDataReader rdr = cmd.ExecuteReader();
cmd.Parameters.Clear();
return rdr;
}
catch
{
conn.Close();
throw;
}
}
/// <summary>
/// 将 System.Data.OleDb.OleDbCommand.CommandText 发送到 System.Data.OleDb.OleDbCommand.Connection 并生成一个 System.Data.OleDb.OleDbDataReader.
/// </summary>
/// <param name="conn"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static OleDbDataReader ExecuteReader(OleDbConnection conn, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms, ConnectionActionType.AutoDetection);
OleDbDataReader rdr = cmd.ExecuteReader();
cmd.Parameters.Clear();
return rdr;
}
catch
{
conn.Close();
throw;
}
}
/// <summary>
/// 执行查询，并返回查询所返回的结果集中第一行的第一列。忽略其他列或行.
/// </summary>
/// <param name="connString"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static object ExecuteScalar(string connString, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
using (OleDbConnection conn = new OleDbConnection(connString))
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms, ConnectionActionType.Open);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
}
/// <summary>
/// 执行查询，并返回查询所返回的结果集中第一行的第一列。忽略其他列或行.
/// </summary>
/// <param name="conn"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static object ExecuteScalar(OleDbConnection conn, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms, ConnectionActionType.AutoDetection);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
/// <summary>
/// 执行查询，并返回查询所返回的结果数据集.
/// </summary>
/// <param name="connString"></param>
/// <param name="cmdType"></param>
/// <param name="cmdText"></param>
/// <param name="cmdParms"></param>
/// <returns></returns>
public static DataSet ExecuteDataset(string connString, CommandType cmdType, string cmdText, params OleDbParameter[] cmdParms)
{
OleDbCommand cmd = new OleDbCommand();
using (OleDbConnection conn = new OleDbConnection(connString))
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, cmdParms, ConnectionActionType.Open);
OleDbDataAdapter da = new