public partial class Sales
{

    public string CustomerID { get; set; }

    public string NrOrder { get; set; }

    public LinesSales AllLinesSales { get; set; }
}

public string NameProd { get; set; }

    public douyble Qtd { get; set; }

    public double Price { get; set; }
}
//////////
Type tiposSales = typeof(Sales);
System.Reflection.PropertyInfo[] properties =                 tiposSales.GetProperties();
System.Data.DataTable dtSales  = new System.Data.DataTable();

foreach (System.Reflection.PropertyInfo pi in properties)
{
    dtSales.Columns.Add(pi.Name);
}
...
foreach (Sales pSal in fileSales)
{
    listaSales.Add(pSal);

}

datagrid_ListSales.ItemsSource = listaSales;
///////
//When clicked row...
private void datagrid_ListSales_SelectionChanged(object sender,     SelectionChangedEventArgs e)
{

    LinesSales l_ade = (LinesSales)((datagrid_ListSales.SelectedItem     as System.Data.DataRowView).Row["AllLinesSales"]); <---error

//I want readd all itens subclass LinesSales:
txt_Product = l_ade.Product.ToString();

...