数据库操作基类,实现对Sql数据库的各种操作.

using System;
using System.Web;
using System.Data;
using System.Data.OleDb;
using System.Configuration;

namespace 4ec
{

/// <summary>
/// 数据库操作基类
/// 实现对Sql数据库的各种操作
/// 创建时间：2007-3-30
/// </summary>
public class SqlDataBase
{
//获取Web.Config数据库连接字符串
private readonly string OleDbConnectionString = "Provider = Microsoft.Jet.OleDb.4.0; Data Source = " + HttpContext.Current.Server.MapPath(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);

private OleDbConnection cn; //创建SQL连接
private OleDbDataAdapter sda; //创建SQL数据适配器
private OleDbDataReader sdr; //创建SQL数据读取器
private OleDbCommand cmd; //创建SQL命令对象
// private OleDbParameter param; //创建SQL参数
private DataSet ds; //创建数据集
private DataView dv; //创建视图

/// <summary>
/// 打开数据库连接
/// </summary>
public void Open()
{
#region
cn = new OleDbConnection(OleDbConnectionString);
cn.Open();
#endregion
}

/// <summary>
/// 关闭数据库连接
/// </summary>
public void Close()
{
#region
if (cn != null)
{
cn.Close();
cn.Dispose();
}
#endregion
}

/// <summary>
/// 返回DataSet数据集
/// </summary>
/// <param name="strSql">SQL语句</param>
public DataSet GetDs(string strSql)
{
#region
Open();
sda = new OleDbDataAdapter(strSql, cn);
ds = new DataSet();
sda.Fill(ds);
Close();
return ds;
#endregion
}

/// <summary>
/// 添加DataSet表
/// </summary>
/// <param name="ds">DataSet对象</param>
/// <param name="strSql">Sql语句</param>
/// <param name="strTableName">表名</param>
public void GetDs(DataSet ds, string strSql, string strTableName)
{
#region
Open();
sda = new OleDbDataAdapter(strSql, cn);
sda.Fill(ds, strTableName);
Close();
#endregion
}

/// <summary>
/// 返回DataView数据视图
/// </summary>
/// <param name="strSql">Sql语句</param>
public DataView GetDv(string strSql)
{
#region
dv = GetDs(strSql).Tables[0].DefaultView;
return dv;
#endregion
}

/// <summary>
/// 获得DataTable对象
/// </summary>
/// <param name="strSql">SQL语句</param>
/// <returns></returns>
public DataTable GetTable(string strSql)
{
#region
return GetDs(strSql).Tables[0];
#endregion
}

/// <summary>
/// 获得OleDbDataReader对象 使用完须关闭DataReader,关闭数据库连接
/// </summary>
/// <param name="strSql">sql语句</param>
/// <returns></returns>
public OleDbDataReader GetDataReader(string strSql)
{
#region
Open();
cmd = new OleDbCommand(strSql, cn);
sdr = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
return sdr;
#endregion
}

/// <summary>
/// 执行Sql语句
/// </summary>
/// <param name="strSql"></param>
public void RunSql(string strSql)
{
#region
Open();
cmd = new OleDbCommand(strSql, cn);
cmd.ExecuteNonQuery();
Close();
#endregion
}

/// <summary>
/// 执行SQL语句，并返回第一行第一列结果
/// </summary>
/// <param name="strSql">SQL语句</param>
/// <returns></returns>
public string RunSqlReturn(string strSql)
{
#region
string strReturn = "";
Open();
try
{
cmd = new OleDbCommand(strSql, cn);
strReturn = cmd.ExecuteScalar().ToString();
}
catch { }
Close();
return strReturn;
#endregion
}

}

}