c# access oledb helper class

连接Access数据库

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Data.OleDb;

namespace TestAccessDB
{

    public class DBHelper
    {
        protected static OleDbConnection conn = new OleDbConnection();
        protected static OleDbCommand comm = new OleDbCommand();

        public DBHelper()
        {

        }
        static string dbFile = AppDomain.CurrentDomain.BaseDirectory + "\\goods.mdb";

        private static void openConnection()
        {
            if (conn.State == ConnectionState.Closed)
            {
                // conn.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + AppDomain.CurrentDomain.BaseDirectory + dbFile + ";Jet OLEDB:Database PassWord=sa";
                // conn.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source="+ dbFile +";Persist Security Info=False;Jet OLEDB:Database Password=sa;";
                conn.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbFile + ";Persist Security Info=False;";
                comm.Connection = conn;
                try
                {
                    conn.Open();
                }
                catch (Exception e)
                { throw new Exception(e.Message); }

            }

        }
        private static void closeConnection()
        {
            if (conn.State == ConnectionState.Open)
            {
                conn.Close();
                conn.Dispose();
                comm.Dispose();
            }
        }
        /// <summary>
        /// 执行sql语句
        /// </summary>
        /// <param name="sqlstr"></param>
        public static int ExecuteNonQuery(string sqlstr)
        {
            int i = 0;
            try
            {
                openConnection();
                comm.CommandType = CommandType.Text;
                comm.CommandText = sqlstr;
               i= comm.ExecuteNonQuery();
            }
            catch (Exception e)
            {
                throw new Exception(e.Message);
            }
            finally
            {

                closeConnection();

            }
            return i;
        }

        /// <summary>
        /// 执行sql语句
        /// </summary>
        /// <param name="sqlstr"></param>
        public static object  executeScalarSql(string sqlstr)
        {
            object o;
            try
            {
                openConnection();
                comm.CommandType = CommandType.Text;
                comm.CommandText = sqlstr;
                 o= comm.ExecuteScalar();
            }
            catch (Exception e)
            {
                throw new Exception(e.Message);
            }
            finally
            {

                closeConnection();

            }

            return o;
        }

        public static int batchInsert(int count)
        {

            int cnt = 0;

            try
            {

                for (int i = 1; i <= count; i++)
                {
                    string sqlstr = "insert into article(sourceID,[user],updateDate) values ('454545434','qwertteeeew_gfhfghgfh',#" + DateTime.Now + "#)";

                    openConnection();
                    comm.CommandType = CommandType.Text;
                    comm.CommandText = sqlstr;
                    cnt += comm.ExecuteNonQuery();

                }

            }
            catch (Exception e)
            {
                throw new Exception(e.Message);
            }
            finally
            {

                closeConnection();

            }

            return cnt;

        }

        /// <summary>
        /// 返回指定sql语句的OleDbDataReader对象，使用时请注意关闭这个对象。
        /// </summary>
        /// <param name="sqlstr"></param>
        /// <returns></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语句的OleDbDataReader对象,使用时请注意关闭
        /// </summary>
        /// <param name="sqlstr"></param>
        /// <param name="dr"></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语句的dataset
        /// </summary>
        /// <param name="sqlstr"></param>
        /// <returns></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 e)
            {
                throw new Exception(e.Message);
            }
            finally
            {
                closeConnection();
            }
            return ds;
        }
        /// <summary>
        /// 返回指定sql语句的dataset
        /// </summary>
        /// <param name="sqlstr"></param>
        /// <param name="ds"></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 e)
            {
                throw new Exception(e.Message);
            }
            finally
            {
                closeConnection();
            }
        }
        /// <summary>
        /// 返回指定sql语句的datatable
        /// </summary>
        /// <param name="sqlstr"></param>
        /// <returns></returns>
        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;
        }
        /// <summary>
        /// 返回指定sql语句的datatable
        /// </summary>
        /// <param name="sqlstr"></param>
        /// <param name="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 e)
            {
                throw new Exception(e.Message);
            }
            finally
            {
                closeConnection();
            }
        }
        /// <summary>
        /// 返回指定sql语句的dataview
        /// </summary>
        /// <param name="sqlstr"></param>
        /// <returns></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 e)
            {
                throw new Exception(e.Message);
            }
            finally
            {
                closeConnection();
            }
            return dv;
        }
    }
}