public void ExampleShouldWork() { using (StringWriter sw = new StringWriter()) { TextWriter stdout = Console.Out; Console.SetOut(sw); LicensePlate li1 = new LicensePlate("FI", "ABC-123"); LicensePlate li2 = new LicensePlate("FI", "UXE-465"); LicensePlate li3 = new LicensePlate("D", "B WQ-431"); LicensePlate li4 = new LicensePlate("D", "B WQ-432"); LicensePlate li5 = new LicensePlate("D", "B WQ-433"); VehicleRegistry register = new VehicleRegistry(); register.Add(li1, "Arto"); register.Add(li2, "Arto"); register.Add(li3, "Jürgen"); register.Add(li4, "Jürgen"); register.Add(li5, "Jürgen"); Console.WriteLine("Plates:"); register.PrintLicensePlates(); Console.WriteLine("Owners:"); register.PrintOwners(); Console.SetOut(stdout); string example = "Plates:\nFI ABC-123\nFI UXE-465\nD B WQ-431\nD B WQ-432\nD B WQ-433\nOwners:\nArto\nJürgen\n"; Assert.AreEqual(example, sw.ToString().Replace("\r\n", "\n"), "The example should work!"); } }