With your class design as I understand it, I wrote the following code in a WPF project. I added a listbox called "listbox1" and a button to the form. I believe the following code does what you want, or at least would guide you to the answer.
public class Company
{
public List<Vehicle> Vehicles;
public Company()
{
Vehicles = new List<Vehicle>() { new Vehicle(1), new Vehicle(2), new Vehicle(3) };
}
}
public class Vehicle
{
private string _vehicleNum;
public Vehicle(int num)
{
_vehicleNum = "Vehicle" + num.ToString();
}
public string getDetails()
{
return _vehicleNum;
}
}
Company ACompany = new Company();
public MainWindow()
{
InitializeComponent();
foreach(Vehicle v in ACompany.Vehicles)
listbox1.Items.Add(v.getDetails());
}
private void Button_Click(object sender, RoutedEventArgs e)
{
for (int i = 0; i < listbox1.SelectedItems.Count; i++)
{
foreach(Vehicle v in ACompany.Vehicles)
{
if (String.Equals(v.getDetails(), listbox1.SelectedItems[i].ToString()))
{
ACompany.Vehicles.Remove(v);
break;
}
}
listbox1.Items.Remove(listbox1.SelectedItems[i]);
}
}