WPF DataGrid 遍历 求WPF高手
小弟我用的是WPF，WPF中没有DataGrid,我用的是toolkit中的DataGrid，
在页面中用了toolkit/DataGrid中的DataGridCheckBoxColumn用于多选，
现在想遍历一下DataGrid，看看DataGridCheckBoxColumn列中有哪些选中了，
再把与之相对应选中的CODE拿出来，求方法或代码。
XAML代码
<Custom:DataGrid BorderBrush="Chocolate" Height="486.163" Width="397" Name="dgExam"
AutoGenerateColumns="False"
ColumnHeaderStyle="{StaticResource dgHeaderStyle}"
RowStyle="{StaticResource dgRowStyle}"
CellStyle="{StaticResource dgCellStyle}"
SelectionChanged="dgExam_SelectionChanged"
CanUserAddRows="False"
CanUserResizeRows="False"
IsReadOnly="True" SelectionMode="Extended" >
<Custom:DataGrid.Columns>
<Custom:DataGridCheckBoxColumn x:Name="AllowCheckbox" Header="选择" Width="30" Binding="{Binding ex_no}" ElementStyle="{DynamicResource NoBorderCheckBoxStyle}"
EditingElementStyle="{DynamicResource NoBorderCheckBoxStyle}" IsThreeState="True"> </Custom:DataGridCheckBoxColumn>
</Custom:DataGrid.Columns>
</Custom:DataGrid>

Binding="{Binding ex_no}" 中ex_no是我绑定了数据库中的字段，dgExam.itemssource = datatable;

求WPF高手

[解决办法]

C# code

using System;using System.Collections.Generic;using System.Linq;using System.Net;using System.Windows;using System.Windows.Controls;using System.Windows.Documents;using System.Windows.Input;using System.Windows.Media;using System.Windows.Media.Animation;using System.Windows.Shapes;namespace SLAPPDemo{    public partial class Page : UserControl    {        public static List<ListInformation> pageItems = null;        public Page()        {            InitializeComponent();            DataBind();        }                /// <summary>        /// 设置 DataGrid 的数据源        /// </summary>         private void DataBind()        {                        this.dataGrid.ItemsSource = GetSpecifiedPage();        }        /// <summary>        /// 获取数据源        /// </summary>        private List<ListInformation> GetSpecifiedPage(