对数据库的操作

/*
 * Desinged by Jim Hui(惠永亮)
 * Email :yonglianghui@163.com
 * QQ:23011599
 * Jiangsu China
 * 2010-04-11
*/

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.OleDb;

/// <summary>
/// dbc 的摘要说明
/// </summary>
public class dbc
{
    public dbc()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }
    static string conStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + AppDomain.CurrentDomain.BaseDirectory + "/App_Data/IFuGood.mdb";
    static OleDbConnection con = new OleDbConnection(conStr);

    public static DataTable ExecuteTable(string commandText, OleDbParameter[] paras)
    {
        DataSet ds = new DataSet();
        try
        {
            con.Open();
            OleDbCommand cmd = new OleDbCommand(commandText, con);
            if (paras != null)
            {
                foreach (OleDbParameter para in paras)
                {
                    cmd.Parameters.Add(para);
                }
            }
            OleDbDataAdapter dap = new OleDbDataAdapter(cmd);
            dap.Fill(ds);
        }
        catch (Exception ex)
        {

            throw new Exception(ex.ToString());
        }
        finally
        {
            con.Close();
        }
        return ds.Tables[0];
    }

    public static void ExecuteNoQuery(string commandText, OleDbParameter[] paras)
    {
        try
        {
            con.Open();
            OleDbCommand cmd = new OleDbCommand(commandText, con);
            if (paras != null)
            {
                foreach (OleDbParameter para in paras)
                {
                    cmd.Parameters.Add(para);
                }
            }

            cmd.ExecuteNonQuery();
        }
        catch (Exception ex)
        {

            throw new Exception(ex.ToString());
        }
        finally
        {
            con.Close();
        }

    }

    public static object ExecuteScalar(string commandText, OleDbParameter[] paras)
    {
        object obj = new object();
        try
        {           
            con.Open();
            OleDbCommand cmd = new OleDbCommand(commandText, con);
            if (paras != null)
            {
                foreach (OleDbParameter para in paras)
                {
                    cmd.Parameters.Add(para);
                }
            }
            obj = cmd.ExecuteScalar();
        }
        catch (Exception ex)
        {
            throw new Exception(ex.ToString());
        }
        finally
        {
            con.Close();
        }

        return obj;
    }

}