[wpf] Get selected row item in DataGrid WPF

public IEnumerable<DataGridRow> GetDataGridRows(DataGrid grid)
{
    var itemsSource = grid.ItemsSource as IEnumerable;
    if (null == itemsSource) yield return null;
    foreach (var item in itemsSource)
    {
        var row = grid.ItemContainerGenerator.ContainerFromItem(item) as DataGridRow;
        if (null != row) yield return row;
    }
}

private void DataGrid_Details_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    try
    {           
        var row_list = GetDataGridRows(DataGrid_Details);
        foreach (DataGridRow single_row in row_lis)
        {
            if (single_row.IsSelected == true)
            {
                MessageBox.Show("the row no."+single_row .GetIndex ().ToString ()+ " is selected!");
            }
        }

    }
    catch { }
}