<?xml version="1.0" encoding="utf-8" ?><configuration>    <startup>         <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.1" />    </startup>  <connectionStrings>    <add name="conn" connectionString ="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=db.mdb;Persist Security Info=False" />  </connectionStrings></configuration>

    public class DbHelper    {        public static OleDbConnection getCon(){            string strcon = System.Configuration.ConfigurationManager.ConnectionStrings["conn"].ToString();            return new OleDbConnection(strcon);        }           }

public class Person    {        public string username { get; set; }        public string pwd { get; set; }        public int age { get; set; }        public DateTime createdate { get; set; }        public DateTime updatedate { get; set; }        public string classroom { get; set; }        public int id { get; set; }    }

        private Random rnd = new Random();        private ObservableCollection<Person> list { get; set; }        public MainWindow()        {            InitializeComponent();            add();//添加数据            BindData();//绑定数据            cr.ItemsSource = new List<string> { "一班", "二班", "三班" };        }               public void BindData()        {            using (var conn = DbHelper.getCon())            {                list = new ObservableCollection<Person>(conn.Query<Person>("select * from users").ToList<Person>());            }            this.DataContext = list;        }                public void add()        {            using (var db = DbHelper.getCon())            {                for (int i = 0; i < 10; i++)                {                    db.Execute("insert into users(username,pwd,age,createDate,classroom) values(@username,@pwd,@age,@createDate,@classroom)", new                    {                        username = "张三",                        pwd = "123",                        age = rnd.Next(20),                        createDate=DateTime.Now.ToString(),                        classroom = "一班"                    });                }            }        }

<Window x:Class="WpfApplication3.MainWindow"        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"        Title="MainWindow" Height="350" Width="525">    <Grid>        <Grid.RowDefinitions>            <RowDefinition Height="auto"/>            <RowDefinition Height="*"/>            <RowDefinition Height="auto"/>            <RowDefinition Height="22"/>        </Grid.RowDefinitions>        <TextBlock Text="access数据基本读写操作"></TextBlock>        <DataGrid Grid.Row="1" Name="dg" ItemsSource="{Binding}"  CanUserAddRows="False" AutoGenerateColumns="False">            <DataGrid.Columns>                <DataGridTextColumn Header="姓名" Binding="{Binding username}" Width="100"></DataGridTextColumn>                <DataGridTextColumn Header="密码" Binding="{Binding pwd}"></DataGridTextColumn>                <DataGridTextColumn Header="年龄" Binding="{Binding age}"></DataGridTextColumn>                <DataGridTextColumn Header="添加时间" Binding="{Binding createdate}"></DataGridTextColumn>                <DataGridTextColumn Header="更新时间" Binding="{Binding updatedate}"></DataGridTextColumn>                <DataGridComboBoxColumn x:Name="cr" Header="班级" SelectedItemBinding="{Binding classroom}"></DataGridComboBoxColumn>            </DataGrid.Columns>        </DataGrid>        <WrapPanel Grid.Row="2" DataContext="{Binding ElementName=dg,Path=SelectedItem}">            <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center">                <TextBlock Text="姓名:"/>                <TextBlock  MinWidth="100" Text="{Binding username}"/>            </StackPanel>            <StackPanel Orientation="Horizontal">                <TextBlock Text="密码:"/>                <TextBlock  MinWidth="100" Text="{Binding pwd}"/>            </StackPanel>            <StackPanel Orientation="Horizontal">                <TextBlock Text="年龄:"/>                <TextBlock  MinWidth="100" Text="{Binding age}"/>            </StackPanel>            <StackPanel Orientation="Horizontal">                <TextBlock Text="添加时间:"/>                <TextBlock  MinWidth="100" Text="{Binding createdate}"/>            </StackPanel>            <StackPanel Orientation="Horizontal">                <TextBlock Text="更新时间:"/>                <TextBlock  MinWidth="100" Text="{Binding updatedate}"/>            </StackPanel>            <StackPanel Orientation="Horizontal">                <TextBlock Text="班级:"/>                <TextBlock  MinWidth="100" Text="{Binding classroom}"/>            </StackPanel>        </WrapPanel>        <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Grid.Row="3" >            <Button Content="刷新" Height="22" VerticalAlignment="Top" Click="Button_Click" />            <Button Content="更新" Click="Button_Click_1"/>        </StackPanel>    </Grid></Window>

private void Button_Click(object sender, RoutedEventArgs e)        {            BindData();        }        private void Button_Click_1(object sender, RoutedEventArgs e)        {            var p=dg.SelectedItem as Person;            if (p == null)            {               MessageBox.Show("请选择要更新的行");               return;            }            using (var conn = DbHelper.getCon())            {                conn.Execute("update users set username=@username,pwd=@pwd,age=@age,createdate=@c,updatedate=@u,classroom=@classroom where id=@id", new                {                  username=p.username,pwd=p.pwd,age=p.age,c=p.createdate,u=p.updatedate,classroom=p.classroom ,id=p.id                });                MessageBox.Show("ok");            }        }