Asp.net Access數據訪問通用類

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

namespace SysClassLibrary
{
    /// <summary>
    /// DataAccess 數據訪問類
    /// <description>數據處理基類,調用方式：DataAccess.DataSet((string)sqlstr);或者DataAccess.DataSet((string)sqlstr,ref DataSet ds); </description>
    /// </summary>
    public class DataAccess
    {
        #region 屬性
        protected static OleDbConnection conn = new OleDbConnection();
        protected static OleDbCommand comm = new OleDbCommand();
        #endregion
        public DataAccess()
        {
            //init();
        }
        #region 內部函數 靜態方法中不會執行DataAccess()構造函數

        /// <summary>
        /// 打開數據庫鏈接
        /// </summary>
        private static void openConnection()
        {
            if (conn.State == ConnectionState.Closed)
            {
                //SysConfig.ConnectionString 爲系統配置類中鏈接字符串

                string strDbName = HttpContext.Current.Server.MapPath(@"~/App_Data/BookShop.mdb");

                conn.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + strDbName;
                comm.Connection = conn;
                try
                {
                    conn.Open();
                }
                catch (Exception e)
                {
                    throw new Exception(e.Message);
                }
            }
        }

        /// <summary>
        /// 關閉當前數據庫鏈接
        /// </summary>
        private static void closeConnection()
        {
            if (conn.State == ConnectionState.Open)
                conn.Close();
            conn.Dispose();
            comm.Dispose();
        }
        #endregion

        /// <summary>
        /// 執行Sql查詢語句
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        public static void ExecuteSql(string sqlstr)
        {
            try
            {
                openConnection();
                comm.CommandType = CommandType.Text;
                comm.CommandText = sqlstr;
                comm.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
            finally
            {
                closeConnection();
            }
        }

        /// <summary>
        /// 執行Sql查詢語句並返回第一行的第一條記錄,返回值爲object 使用時須要拆箱操做 -> Unbox
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <returns>object 返回值 </returns>
        public static object ExecuteScalar(string sqlstr)
        {
            object obj = new object();
            try
            {
                openConnection();
                comm.CommandType = CommandType.Text;
                comm.CommandText = sqlstr;
                obj = comm.ExecuteScalar();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
            finally
            {
                closeConnection();
            }
            return obj;
        }

        /// <summary>
        /// 執行Sql查詢語句,同時進行事務處理
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        public static void ExecuteSqlWithTransaction(string sqlstr)
        {
            closeConnection();
            openConnection();

            OleDbTransaction trans;
            trans = conn.BeginTransaction();
            comm.Transaction = trans;
            try
            {
                openConnection();
                comm.CommandType = CommandType.Text;
                comm.CommandText = sqlstr;
                comm.ExecuteNonQuery();
                trans.Commit();
            }
            catch
            {
                trans.Rollback();
            }
            finally
            {
                closeConnection();
            }
        }

        /// <summary>
        /// 返回指定Sql語句的OleDbDataReader，請注意，在使用後請關閉本對象，同時將自動調用closeConnection()來關閉數據庫鏈接
        /// 方法關閉數據庫鏈接
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <returns>OleDbDataReader對象</returns>
        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;
        }

        /// <summary>
        /// 返回指定Sql語句的OleDbDataReader，請注意，在使用後請關閉本對象，同時將自動調用closeConnection()來關閉數據庫鏈接
        /// 方法關閉數據庫鏈接
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <param name="dr">傳入的ref DataReader 對象</param>
        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();
                }
            }
        }

        /// <summary>
        /// 返回指定Sql語句的DataSet
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <returns>DataSet</returns>
        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 ex)
            {
                throw new Exception(ex.Message);
            }
            finally
            {
                closeConnection();
            }
            return ds;
        }

        /// <summary>
        /// 返回指定Sql語句的DataSet
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <param name="ds">傳入的引用DataSet對象</param>
        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 ex)
            {
                throw new Exception(ex.Message);
            }
            finally
            {
                closeConnection();
            }
        }
        /// <summary>
        /// 返回指定Sql語句的DataTable
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <returns>DataTable</returns>
        public static DataTable DataTable(string sqlstr)
        {
            OleDbDataAdapter da = new OleDbDataAdapter();
            DataTable Datatable = new DataTable();
            try
            {
                openConnection();
                comm.CommandType = CommandType.Text;
                comm.CommandText = sqlstr;
                da.SelectCommand = comm;
                da.Fill(Datatable);
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
            finally
            {
                closeConnection();
            }
            return Datatable;
        }

        /// <summary>
        /// 執行指定Sql語句,同時給傳入DataTable進行賦值
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <param name="dt">ref DataTable dt </param>
        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 ex)
            {
                throw new Exception(ex.Message);
            }
            finally
            {
                closeConnection();
            }
        }

        /// <summary>
        /// 返回指定Sql語句的DataView
        /// </summary>
        /// <param name="sqlstr">傳入的Sql語句</param>
        /// <returns>DataView</returns>
        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 ex)
            {
                throw new Exception(ex.Message);
            }
            finally
            {
                closeConnection();
            }
            return dv;
        }
    }

}