void BillingEngine_EinvNodeAdded(object sender, MercatorUi.Engine.Gescom.BillingEngine.EinvNodeAddedEventArgs e)
{
    if ((e.Node.Name == "cbc:ID") && (e.ParentNode.Name == "cac:SellersItemIdentification"))
        e.Node.InnerText = e.DrLigne["s_cle1"].ToString();
}