通用数据访问层--Access版

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

using System.Data.OleDb; 


namespace GetDBMo{ 
    class GetDbMo 
    { 
        protected static OleDbConnection conn = new OleDbConnection(); 
        protected static OleDbCommand comm = new OleDbCommand(); 
        private static void openConnection() 
        { 
            if (conn.State == ConnectionState.Closed) 
            { 
                conn.ConnectionString = @"Provider=Microsoft.Jet.OleDb.4.0;Data Source="+Settings.Default.DbPath ;//web.config文件里设定。 
                comm.Connection = conn; 
                try 
                { 
                    conn.Open(); 
                } 
                catch (Exception e) 
                { throw new Exception(e.Message); } 

            } 

        }//打开数据库 

        private static void closeConnection() 
        { 
            if (conn.State == ConnectionState.Open) 
            { 
                conn.Close(); 
                conn.Dispose(); 
                comm.Dispose(); 
            } 
        }//关闭数据库 

        public static void excuteSql(string sqlstr) 
        { 
            try 
            { 
                openConnection(); 
                comm.CommandType = CommandType.Text; 
                comm.CommandText = sqlstr; 
                comm.ExecuteNonQuery(); 
            } 
            catch (Exception e) 
            { 
                throw new Exception(e.Message); 
            } 
            finally 
            { closeConnection(); } 
        }//执行sql语句 

        public static OleDbDataReader dataReader(string sqlstr) 
        { 
            OleDbDataReader dr = null; 
            try 
            { 
                openConnection(); 
                comm.CommandText = sqlstr; 
                comm.CommandType = CommandType.Text; 

                dr = comm.ExecuteReader(CommandBehavior.CloseConnection); 
            } 
            catch 
            { 
                try 
                { 
                    dr.Close(); 
                    closeConnection(); 
                } 
                catch { } 
            } 
            return dr; 
        }//返回指定sql语句的OleDbDataReader对象，使用时请注意关闭这个对象。 
        public static void dataReader(string sqlstr, ref OleDbDataReader dr) 
        { 
            try 
            { 
                openConnection(); 
                comm.CommandText = sqlstr; 
                comm.CommandType = CommandType.Text; 
                dr = comm.ExecuteReader(CommandBehavior.CloseConnection); 
            } 
            catch 
            { 
                try 
                { 
                    if (dr != null && !dr.IsClosed) 
                        dr.Close(); 
                } 
                catch 
                { 
                } 
                finally 
                { 
                    closeConnection(); 
                } 
            } 
        }//返回指定sql语句的OleDbDataReader对象,使用时请注意关闭 

        public static DataSet dataSet(string sqlstr) 
        { 
            DataSet ds = new DataSet(); 
            OleDbDataAdapter da = new OleDbDataAdapter(); 
            try 
            { 
                openConnection(); 
                comm.CommandType = CommandType.Text; 
                comm.CommandText = sqlstr; 
                da.SelectCommand = comm; 
                da.Fill(ds); 

            } 
            catch (Exception e) 
            { 
                throw new Exception(e.Message); 
            } 
            finally 
            { 
                closeConnection(); 
            } 
            return ds; 
        }//返回指定sql语句的dataset 

        public static void dataSet(string sqlstr, ref DataSet ds) 
        { 
            OleDbDataAdapter da = new OleDbDataAdapter(); 
            try 
            { 
                openConnection(); 
                comm.CommandType = CommandType.Text; 
                comm.CommandText = sqlstr; 
                da.SelectCommand = comm; 
                da.Fill(ds); 
            } 
            catch (Exception e) 
            { 
                throw new Exception(e.Message); 
            } 
            finally 
            { 
                closeConnection(); 
            } 
        }//返回指定sql语句的dataset 

        public static DataTable dataTable(string sqlstr) 
        { 
            DataTable dt = new DataTable(); 
            OleDbDataAdapter da = new OleDbDataAdapter(); 
            try 
            { 
                openConnection(); 
                comm.CommandType = CommandType.Text; 
                comm.CommandText = sqlstr; 
                da.SelectCommand = comm; 
                da.Fill(dt); 
            } 
            catch (Exception e) 
            { 
                throw new Exception(e.Message); 
            } 
            finally 
            { 
                closeConnection(); 
            } 
            return dt; 
        }//返回指定sql语句的datatable 
        public static void dataTable(string sqlstr, ref DataTable dt) 
        { 
            OleDbDataAdapter da = new OleDbDataAdapter(); 
            try 
            { 
                openConnection(); 
                comm.CommandType = CommandType.Text; 
                comm.CommandText = sqlstr; 
                da.SelectCommand = comm; 
                da.Fill(dt); 
            } 
            catch (Exception e) 
            { 
                throw new Exception(e.Message); 
            } 
            finally 
            { 
                closeConnection(); 
            } 
        }//返回指定sql语句的datatable 

        public static DataView dataView(string sqlstr) 
        { 
            OleDbDataAdapter da = new OleDbDataAdapter(); 
            DataView dv = new DataView(); 
            DataSet ds = new DataSet(); 
            try 
            { 
                openConnection(); 
                comm.CommandType = CommandType.Text; 
                comm.CommandText = sqlstr; 
                da.SelectCommand = comm; 
                da.Fill(ds); 
                dv = ds.Tables[0].DefaultView; 
            } 
            catch (Exception e) 
            { 
                throw new Exception(e.Message); 
            } 
            finally 
            { 
                closeConnection(); 
            } 
            return dv; 
        } 
        //返回指定sql语句的dataview 

    } 
}