// logic for find existing customer button. Returns a list of existing customers in a combo box
        // that match specified name
        private void btnSearch_Click(object sender, RoutedEventArgs e)
        {
            comBoxSearchResult.Items.Clear();
            if (txtBoxSearchName.Text == String.Empty)
            {
                MessageBox.Show("Please proivde a name you wish to search for.");
                return;
            }
            string findCustomer = txtBoxSearchName.Text.ToLower();

            foreach (var customer in DataLayerFacade.FindCustomerByName(findCustomer))
            {
                comBoxSearchResult.Items.Add(customer.Name);
            }
            comBoxSearchResult.IsDropDownOpen = true;
        }