asp.net 数据库连接

  <appSettings>
   <add key="db" value="data/data.asa"></add>
   <add key="db1" value="../data/data.asa"></add>
 </appSettings>
  <system.web>
引用
string str="Provider=Microsoft.Jet.Oledb.4.0;Data Source=" + System.Web.HttpContext.Current.Server.MapPath(ConfigurationSettings.AppSettings["db"]);

    public static void ExecuteSqlStr(string str)
        {    
            OleDbConnection conn=new OleDbConnection(GetConStr());
            conn.Open();
            OleDbTransaction Tran=conn.BeginTransaction();            //启用事务    
            try
            {  
                OleDbCommand cmd=new OleDbCommand(str,conn);
                cmd.Transaction=Tran;
                cmd.ExecuteNonQuery();
                Tran.Commit();                                        //提交事务
                cmd.Dispose();
                conn.Close();
            }
            catch(OleDbException ex)
            {
                Tran.Rollback();                                    //回滚事务
                System.Web.HttpContext.Current.Response.Write("<script>alert('"+ex.Message.ToString()+"');history.back();</script>");
                System.Web.HttpContext.Current.Response.End();
            }
        
        }