DataGrid中的WPF双重排序

<DataGrid x:Name="myDataGrid" AutoGenerateColumns="False">
    <!-- 列定义 -->
</DataGrid>

List<MyData> dataList = new List<MyData>();
// 添加数据到dataList
myDataGrid.ItemsSource = dataList;

<DataGrid.Columns>
    <DataGridTextColumn Header="列1" Binding="{Binding Property1}" />
    <DataGridTextColumn Header="列2" Binding="{Binding Property2}" />
    <!-- 其他列 -->
</DataGrid.Columns>

myDataGrid.Sorting += MyDataGrid_Sorting;

private void MyDataGrid_Sorting(object sender, DataGridSortingEventArgs e)
{
    // 获取要排序的列
    DataGridColumn column = e.Column;

    // 清除已有的排序描述
    myDataGrid.Items.SortDescriptions.Clear();

    // 添加第一个排序描述
    SortDescription sortDescription1 = new SortDescription("Property1", ListSortDirection.Ascending);
    myDataGrid.Items.SortDescriptions.Add(sortDescription1);

    // 添加第二个排序描述
    SortDescription sortDescription2 = new SortDescription("Property2", ListSortDirection.Descending);
    myDataGrid.Items.SortDescriptions.Add(sortDescription2);

    // 取消默认的排序
    e.Handled = true;
}