观察者模式--初学入门

理解不是很深，不做解说，自己写了个小例子记录下来

例子以面试者去面试为主题，容易理解，例子简单(小白写的，能不简单吗),能看的懂的代码才是好代码啊

观察者接口

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace ConsoleApplication1
 8 {
 9     /// <summary>
10     /// 观察者接口
11     /// </summary>
12     interface IMSG
13     {
14         /// <summary>
15         /// 出题
16         /// </summary>
17         void ShowMessage();
18         /// <summary>
19         /// 结果
20         /// </summary>
21         void Result();
22     }
23 }

View Code

观察者

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace ConsoleApplication1
 8 {
 9     /// <summary>
10     /// 面试管
11     /// </summary>
12     public class MSG : IMSG
13     {
14         /// <summary>
15         /// 面试状态
16         /// </summary>
17         public string state { get; set; }
18         public GCZ_abstract gcz { get; set; }//面试者
19         private List<GCZ_abstract> works = new List<GCZ_abstract>();//所有面试人员
20         /// <summary>
21         /// 添加面试人员
22         /// </summary>
23         /// <param name="gcz"></param>
24         public void Add(GCZ_abstract gcz)
25         {
26             works.Add(gcz);
27         }
28         /// <summary>
29         /// 删除面试人员
30         /// </summary>
31         /// <param name="gcz"></param>
32         public void Remove(GCZ_abstract gcz)
33         {
34             works.Remove(gcz);
35         }
36         public void ShowMessage()
37         {
38             Console.WriteLine("欢迎来面试，我出题了。。。
");
39         }
40 
41         /// <summary>
42         /// 面试结果
43         /// </summary>
44         public void Result()
45         {
46             foreach(GCZ_abstract man in works)
47             {
48                 man.GX();
49             }
50         }
51     }
52 }

View Code

订阅类型

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace ConsoleApplication1
 8 {
 9     /// <summary>
10     /// 面试人员集合
11     /// </summary>
12     public abstract class GCZ_abstract
13     {
14         /// <summary>
15         /// 面试感想
16         /// </summary>
17         public abstract void GX();
18     }
19 }

View Code

类型一(订阅者)

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace ConsoleApplication1
 8 {
 9     /// <summary>
10     /// 具体观察者类型(面试人员)
11     /// </summary>
12     public class GCZ1 : GCZ_abstract
13     {
14         private MSG msg { get; set; }
15         public GCZ1(MSG msg)
16         {
17             this.msg = msg;
18         }
19 
20         public override void GX()
21         {
22             if (msg.state == "1")
23             {
24                 Console.WriteLine("面试官来了，很激动！");
25             }
26             else if (msg.state == "2") 
27             {
28                 Console.WriteLine("面试官还没来，很紧张！");
29             }
30             else
31                 Console.WriteLine("面试官结束了，轻松！");
32         }
33     }
34 }

View Code

类型二(订阅者)

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace ConsoleApplication1
 8 {
 9     /// <summary>
10     /// 具体观察者类型(面试人员)
11     /// </summary>
12     public class GCZ2 : GCZ_abstract
13     {
14         private MSG msg { get; set; }
15         public GCZ2(MSG msg)
16         {
17             this.msg = msg;
18         }
19 
20         public override void GX()
21         {
22             if (msg.state == "1")
23             {
24                 Console.WriteLine("面试官来了，我不动明王！");
25             }
26             else if (msg.state == "2")
27             {
28                 Console.WriteLine("面试官还没来，我不动明王！");
29             }
30             else
31                 Console.WriteLine("面试结束，我面不改色！");
32         }
33     }
34 }

View Code

结果

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace ConsoleApplication1
 8 {
 9     class Program
10     {
11         static void Main(string[] args)
12         {
13             MSG msg = new MSG();//面试的面试官
14             msg.ShowMessage();//面试官出题
15             //面试中
16             GCZ1 one = new GCZ1(msg);//面试者1
17             msg.Add(one);
18             GCZ2 two = new GCZ2(msg);//面试者2
19             msg.Add(two);
20 
21             msg.state = "2";//面试状态
22             msg.Result();
23         }
24     }
25 }

View Code