private void BtnProductToevoegen_Click(object sender, RoutedEventArgs e) { var x = TbPrijs.Text; var replace = x.Replace('.', ','); var d = decimal.Parse(replace); var product = new Webshop(TbNaam.Text, d); _dierAsiel.AddProduct(product); _listViewProducten.Items.Clear(); foreach (var p in _dierAsiel.WebshopList) { _listViewProducten.Items.Add(p); } this.Close(); }