public void CustomerInitialize()
 {
     if (!customerInitialied)
     {
         Customer lars = new Customer("anders", "Odensevej 17", 5000, "Odense", 23, 47583928, "*****@*****.**");
         Customer jens = new Customer("jens", "Vejlevej 2", 5000, "Odense", 45, 83619374, "*****@*****.**");
         customerList.Add(lars);
         customerList.Add(jens);
         listBCustomers.ItemsSource = customerList;
         customerInitialied = true;
     }
 }
 //a customer gets added to the list, the list is refreshed and the customer is saved in the json customer file
 private void btnSaveUser_Click(object sender, RoutedEventArgs e)
 {
     try
     {
         Customer newCustomer = new Customer(txtNewUserFullName.Text, txtNewUserAdress.Text, int.Parse(txtNewUserZipCode.Text), txtNewUserCity.Text, age, int.Parse(txtNewUserTelehone.Text), txtNewUserEmail.Text);
         customerList.Add(newCustomer);
         listBCustomers.Items.Refresh();
         //SaveCustomers(newCustomer);
         SaverAndLoader.ObjectToJsonString(customerList);
         ClearTextBoxes();
     }
     catch
     {
         MessageBox.Show("Alle input skal være korrekt format!");
     }
 }