这两天写了个类。针对Sql server和OLE数据库所写的。源码如下：

\Classes\DbControl.cs
==========================================================

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.OleDb;

namespace GuestBook
{
/// <summary>
/// DbControl 的摘要描述。
/// </summary>
public class DbControl:Classes.DataBaseType.DbOpen
{
//類成員定義。
private int record_total = 0;
protected string DBTYPE,SQL_SELECT;
protected SqlConnection sqlConn;
protected OleDbConnection oleConn;
protected SqlCommand sqlCmd;
protected OleDbCommand oleCmd;
protected DataSet ds = new DataSet();

public int RecordTotal
{
get
{
switch (DBTYPE)
{
case "SQL":
sqlCmd.Cancel();
sqlCmd.CommandText = SQL_SELECT;
SqlDataReader sqlDr;
sqlDr = sqlCmd.ExecuteReader();
while (sqlDr.Read())
{
record_total++;
}
sqlDr.Close();
break;
case "OLE":
oleCmd.Cancel();
oleCmd.CommandText = SQL_SELECT;
OleDbDataReader oleDr;
oleDr = oleCmd.ExecuteReader();
while (oleDr.Read())
{
record_total++;
}
oleDr.Close();
break;
}
return record_total;
}
}

public DbControl(string dbType,string dbName)
{
//重載構造函數。
DBTYPE = dbType.ToUpper();
switch (dbType.ToUpper())
{
case "SQL":
sqlConn = this.SqlConnect(dbName);
oleConn.Close();
oleConn.Dispose();
break;
case "OLE":
oleConn = this.OleConnect(dbName);
oleConn.Close();
oleConn.Dispose();
break;
}
}

public DbControl():base()
{
//
// TODO: 在這裡加入建構函式的程式碼
//
}

public void Open(string dbType,string dbName)
{
//數據庫文件打開。
DBTYPE = dbType.ToUpper();
switch (dbType.ToUpper())
{
case "SQL":
sqlConn = this.SqlConnect(dbName);
break;
case "OLE":
oleConn = this.OleConnect(dbName);
break;
}
}

public SqlDataReader SqlGetReader(string strQuery)
{
//返回一個SqlDataReader。用於Sql server
SQL_SELECT = strQuery;
sqlCmd = new SqlCommand(strQuery,sqlConn);
SqlDataReader dr;
try
{
sqlCmd.Connection.Open();
}
catch (Exception e)
{
throw e;
}
dr = sqlCmd.ExecuteReader();
return dr;
}

public OleDbDataReader OleGetReader(string strQuery)
{
//返回一個OleDbDataReader。用於OleDb
SQL_SELECT = strQuery;
oleCmd = new OleDbCommand(strQuery,oleConn);
OleDbDataReader dr;
try
{
oleCmd.Connection.Open();
}
catch (Exception e)
{
throw e;
}
dr = oleCmd.ExecuteReader();
return dr;
}

public int SqlRunCommand(string strQuery)
{
//執行一條SQL語句。包括記錄插入、更新、刪除。用於Sql server
SQL_SELECT = strQuery;
sqlCmd = new SqlCommand(strQuery,sqlConn);
try
{
sqlCmd.Connection.Open();
}
catch (Exception e)
{
throw e;
}
return sqlCmd.ExecuteNonQuery();
}

public int OleRunCommand(string strQuery)
{
//執行一條SQL語句。包括記錄插入、更新、刪除。用於OleDb
SQL_SELECT = strQuery;
oleCmd = new OleDbCommand(strQuery,oleConn);