WPF Datagrid SelectionChanged事件和实体框架

在WPF应用程序中，我有一个datagrid，其中包含来自实体框架请求的数据

方法：

public static void GetArticlesDisposCommandes(DataGrid dt,string artCodeForms,string artCodeERP)
{
    using (GSUITEEntities dc = new GSUITEEntities())
    {
        dt.ItemsSource = (from a in dc.GCSTOCK
                          join b in dc.FICHES_ARTICLES on a.STO_COD_ART equals b.ART_CODE
                          where (b.ART_CODE == artCodeForms || b.ART_CODE == artCodeERP)
                             && !a.STO_NUMPAL.StartsWith("FDR")
                             && a.STO_PICKING != null
                             && a.STO_OUTDATE == null
                             && a.STO_PRECO == 0
                          select new
                             {
                                 a.STO_ID,
                                 b.ART_CODE,
                                 b.ART_LIBELLE1,
                                 a.STO_NUMPAL,
                                 a.STO_PICKING,
                                 a.STO_PNET,
                                 a.STO_DATECONG,
                                 a.STO_DLUO,
                                 a.LOT_ID,
                                 a.STO_LOT1
                             }).ToList();
    }
}

xaml标记：