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();
        }