private void navEdit_ElementClick(object sender, DevExpress.XtraBars.Navigation.NavElementEventArgs e)
        {
            frmAfdekmateriaal f = new frmAfdekmateriaal(int.Parse(gcCP.GetFocusedRowCellValue("AfdekID").ToString()));

            f.ShowDialog();
            gcSuppliers.DataSource = cls.GetAllAfdekmateriaal();
        }
        private void navAdd_ElementClick(object sender, DevExpress.XtraBars.Navigation.NavElementEventArgs e)
        {
            frmAfdekmateriaal f = new frmAfdekmateriaal(0);

            f.ShowDialog();
            gcSuppliers.DataSource = cls.GetAllAfdekmateriaal();
        }