private void AgregarRenglon()
{
//Agregar detalle de la factura.
ChildRows = (DataRowView)bsitem.AddNew();
ChildRows.BeginEdit();
ChildRows["numero"] = txt_numero_despacho.Text;
ChildRows["cant"] = 0;
ChildRows["ratio"] = 0;
ChildRows["width"] = 0;
ChildRows["msi"] = 0;
ChildRows["kilo_rollo"] = 0;
ChildRows["precio"] = 0.0;
ChildRows["total_renglon"] = 0;
ChildRows.Row.SetParentRow(ParentRow.Row);
ChildRows.EndEdit();
bsitem.Position = bsitem.Count - 1;
ContadorRegistros();
}