检索wpf中的所有datagrid行

Question

我有一个数据网格如下;

mainWindow.xaml：

    <DataGrid Name="CSVDataGrid" ItemsSource="{Binding}" AutoGenerateColumns="False" Margin="20,5,0,0"  HorizontalAlignment="Left"
              Grid.ColumnSpan="4" Grid.Row="3" Grid.Column="0" SelectionChanged="CSVDataGrid_SelectionChanged" Width="560">
        <DataGrid.Columns>
            <DataGridTextColumn Binding="{Binding Project}" Header="Project" Width="50" />
            <DataGridTextColumn Binding="{Binding Description}" Header="Description" Width="200"/>
        </DataGrid.Columns>
    </DataGrid>

MainWindow.xaml.cs

    private void SubmitBtn_Click(object sender, RoutedEventArgs e)
    {
        for (int i = 0; i < CSVDataGrid.Items.Count; i++)
        {
            DataGridRow row = (DataGridRow) CSVDataGrid.ItemContainerGenerator.ContainerFromIndex(i);
            if (row != null)
            {
                object[] itemArray = ((System.Data.DataRowView) (row.Item)).Row.ItemArray;
                MessageBox.Show(String.Format("Row = {0},{1},{3}",
                                              itemArray[0].ToString(),
                                              itemArray[1].ToString(),
                                                                            i));
            }
        }
    }

当用户点击按钮时，我想检索每一行的数据。目前，这仅适用于可见行。我怎样才能获得所有数据？