silverlight DataGrid 添加删除列/删除按钮

<sdk:DataGrid x:Name="DataGrid1" HorizontalAlignment="Center"  VerticalAlignment="Top"  Margin="0,41,0,0" AutoGenerateColumns="False"  IsReadOnly="True">
<sdk:DataGrid.Columns>
<sdk:DataGridTextColumn Header="id" Binding="{Binding ID}"/>
<sdk:DataGridTextColumn Header="用户名" Binding="{Binding UserName}"/>
<sdk:DataGridTextColumn Header="BirtherDate" Binding="{Binding BirtherDate,StringFormat=yyyy-MM-dd HH:mm:ss}"/>
<sdk:DataGridTextColumn Header="Height" Binding="{Binding Height}"/>
<sdk:DataGridTextColumn Header="Sex" Binding="{Binding Sex}"/>
<sdk:DataGridTemplateColumn Width="60"  Header="删除">
<sdk:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<Button Content="删除"  Click="Button_Click_del" Width="55" />
</DataTemplate>
</sdk:DataGridTemplateColumn.CellTemplate>
</sdk:DataGridTemplateColumn>
</sdk:DataGrid.Columns>
</sdk:DataGrid>

private void Button_Click_del(object sender, RoutedEventArgs e)
{
Button b = sender as Button;
Person P = (Person)b.DataContext;//获取当前数据
if (P!=null)
{
client.DeleteAsync(P);//删除
}
}