状态模式（Statue）

天才白痴书馆 2015-04-16

展开全文

状态模式：当一个对象的内在状态改变时运行改变其行为，这个对象看起来像是改变了其类。

状态模式结构

<喎?"http://www./kf/ware/vc/" target="_blank" class="keylink">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"http://www./uploadfile/Collfiles/20140322/20140322082740134.jpg" alt="\">

本例中状态只有两个，不能概括那种状态转换过于复杂的情况，但本例主要是用来表示状态模式的。

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
namespace 电灯的状态
{

    //抽象状态类
    abstract class LightState
    {
        public abstract void PressSwitch(Light light); //按下按钮
    }
    //电灯打开状态类
    class LightOn : LightState
    {
        public override void PressSwitch(Light light)
        {

            light.State = new LightOff();
            Console.WriteLine("电灯已关");

        }
    }
    //电灯关闭状态类
    class LightOff : LightState
    {
        public override void PressSwitch(Light light)
        {

            light.State = new LightOn();
            Console.WriteLine("电灯已开");
        }
    }
    //电灯类
    class Light
    {
        private LightState state;
        public LightState State
        {
            get { return state; }
            set { state = value; }
        }
        public Light(LightState state) //构造时设置初始状态
        {
            this.state = state;
        }
        public void PressLightSwitch()
        {
            state.PressSwitch(this); //转换本类的状态
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            Light light = new Light(new LightOn()); //打开状态
            //反复开关。。。
            light.PressLightSwitch();
            light.PressLightSwitch();
            light.PressLightSwitch();
            light.PressLightSwitch();
            light.PressLightSwitch();
        }
    }