C# 操作 access 数据库

随笔：

（1）   命名空间

using System.Data.OleDb;

（2）   连接字符串

private staticstring connStr = @"Provider= Microsoft.Ace.OLEDB.12.0;Data Source = d:\login.accdb";

注意：

a、DataSource = 数据库存放的路径（这里数据库放到了D盘目录下）

b、 2003版本的Access数据库链接字符串：  privatestatic stringconnStr =@"Provider = Microsoft.Jet.OLEDB.4.0;DataSource = d:\login.mdb";

2007版本的Access数据库链接字符串：privatestaticstring connStr =@"Provider= Microsoft.Ace.OLEDB.12.0;Data Source = d:\login.accdb";

（3）   建立连接：

OleDbConnection tempconn =new OleDbConnection(connStr);

（4）   使用OleDbCommand类来执行Sql语句：

OleDbCommand cmd = new OleDbCommand(sql, tempconn);

tempconn.Open();

cmd.ExecuteNonQuery();

栗子（工具类）：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Data.OleDb;

using System.Windows.Forms;

using System.Data;

namespace test

{

    class AccessHelper

    {

        private static string connStr = @"Provider = Microsoft.Ace.OLEDB.12.0;Data Source = d:\login.accdb";

        public static OleDbConnection GetConn()

        {

            OleDbConnection tempconn = new OleDbConnection(connStr);

            MessageBox.Show(tempconn.DataSource);

            tempconn.Open();

            MessageBox.Show(tempconn.State.ToString());

            return (tempconn);

        }

        /// <summary>

        /// 执行增加、删除、修改指令

        /// </summary>

        /// <param name="sql">增加、删除、修改的sql语句</param>

        /// <param name="param">sql语句的参数</param>

        /// <returns></returns>

        public static int ExecuteNonQuery(string sql, params OleDbParameter[] param)

        {

            using (OleDbConnection conn = new OleDbConnection(connStr))

            {

                using (OleDbCommand cmd = new OleDbCommand(sql,conn))

                {

                    if (param != null)

                    {

                        cmd.Parameters.AddRange(param);

                    }

                    conn.Open();

                    return(cmd.ExecuteNonQuery());

                }

            }

        }

        /// <summary>

        /// 执行查询指令，获取返回的首行首列的值

        /// </summary>

        /// <param name="sql">查询sql语句</param>

        /// <param name="param">sql语句的参数</param>

        /// <returns></returns>

        public static object ExecuteScalar(string sql, params OleDbParameter[] param)

        {

            using (OleDbConnection conn = new OleDbConnection(connStr))

            {

                using (OleDbCommand cmd = new OleDbCommand(sql, conn))

                {

                    if (param != null)

                    {

                        cmd.Parameters.AddRange(param);

                    }

                    conn.Open();

                    return (cmd.ExecuteScalar());

                }

            }

        }

        /// <summary>

        /// 执行查询指令，获取返回的datareader

        /// </summary>

        /// <param name="sql">查询sql语句</param>

        /// <param name="param">sql语句的参数</param>

        /// <returns></returns>

        public static OleDbDataReader ExecuteReader(string sql, params OleDbParameter[] param)

        {

            OleDbConnection conn = new OleDbConnection(connStr);

            OleDbCommand cmd = conn.CreateCommand();

            cmd.CommandText = sql;

            cmd.CommandType = CommandType.Text;

            if (param != null)

            {

                cmd.Parameters.AddRange(param);

            }

            conn.Open();

            return (cmd.ExecuteReader(CommandBehavior.CloseConnection));

        }

        /// <summary>

        /// 执行查询指令，获取返回datatable

        /// </summary>

        /// <param name="sql">查询sql语句</param>

        /// <param name="param">sql语句的参数</param>

        /// <returns></returns>

        public static DataTable ExecuteDatable(string sql, params OleDbParameter[] param)

        {

            using (OleDbConnection conn = new OleDbConnection(connStr))

            {

                using (OleDbCommand cmd = new OleDbCommand(sql, conn))

                {

                    if (param != null)

                    {

                        cmd.Parameters.AddRange(param);

                    }

                    DataTable dt = new DataTable();

                    OleDbDataAdapter sda = new OleDbDataAdapter(cmd);

                    sda.Fill(dt);

                    return (dt);

                }

            }

        }

    }

}