C#中的Virtual、Override和new关键词理解

 1 using System;  
 2 using System.Collections.Generic;  
 3   
 4   
 5 public class Car  
 6 {  
 7   
 8     public virtual void DescribeCar()  
 9     {  
10         Console.WriteLine("Base Car!");  
11     }  
12   
13 }  
14   
15   
16 public class ConvertibleCar : Car  
17 {  
18     public new void DescribeCar()  
19     {  
20         base.DescribeCar();  
21         Console.WriteLine("Convertible Car!");  
22     }  
23 }  
24   
25 public class DerivedConvertibleCar : ConvertibleCar  
26 {  
27     public new void DescribeCar()  
28     {  
29         base.DescribeCar();  
30         Console.WriteLine("DerivedConvertibleCar Car!");  
31     }  
32 }  
33   
34   
35 public class DerivedMinivan : Minivan  
36 {  
37     public override void DescribeCar()  
38     {  
39         base.DescribeCar();  
40         Console.WriteLine("DerivedMinivan Car!");  
41     }  
42 }  
43 public class Minivan : Car  
44 {  
45     public override void DescribeCar()  
46     {  
47         base.DescribeCar();  
48         Console.WriteLine("Minivan Car!");  
49     }  
50 }  
51   
52   
53 public class CarCollections  
54 {  
55     public static void Main()  
56     {  
57         List<CAR> cars = new List<CAR>();  
58   
59         cars.Add(new Car());  
60         cars.Add(new ConvertibleCar());  
61         cars.Add(new Minivan());  
62         cars.Add(new DerivedConvertibleCar());  
63         cars.Add(new DerivedMinivan());  
64         foreach (Car car in cars)  
65             car.DescribeCar();  
66     }  
67 }  

Base Car!【Car】
Base Car!【ConvertibleCar】
Base Car!【Minivan】
Minivan Car!
Base Car!【DerivedConvertibleCar】
Base Car!【DerivedMinivan 】
Minivan Car!
DerivedMinivan Car!