MEF 初识

代码如下：

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.ComponentModel.Composition;
 6 using System.ComponentModel.Composition.Hosting;
 7 
 8 namespace meftest001
 9 {
10     class Program
11     {
12         static void Main(string[] args)
13         {
14             var demo = new DemoOne();
15             demo.Run("1");
16             Console.WriteLine("----");
17             demo.Run("2");
18             Console.ReadLine();
19         }
20     }
21 
22     /// <summary>
23     /// 公用的 组装 处理
24     /// </summary>
25     public abstract class BassClass
26     {
27         public BassClass()
28         {
29             var catalog = new AggregateCatalog();
30             catalog.Catalogs.Add(new AssemblyCatalog(typeof(Program).Assembly));
31             var _container = new CompositionContainer(catalog);
32             _container.ComposeParts(this);
33         }
34     }
35     public interface DemoOneInterface
36     {
37         void Send(string msg);
38     }
39 
40     /// <summary>
41     /// 导入
42     /// </summary>
43     public class DemoOne : BassClass
44     {
45         [ImportMany("lyb")]
46         IEnumerable<Lazy<DemoOneInterface, DemoOneInterfaceDepict>> DOlist;
47         public void Run(string type)
48         {
49             foreach (var _do in DOlist.Where(item => item.Metadata.Depict == type))
50             {
51                 _do.Value.Send("DemoOne.Send");
52             }
53         }
54     }
55     /// <summary>
56     /// 导出
57     /// </summary>
58     [Export("lyb", typeof(DemoOneInterface))]
59     [ExportMetadata("Depict", "1")]
60     public class DemoOneInherit1 : DemoOneInterface
61     {
62         public void Send(string msg)
63         {
64             Console.WriteLine("DemoOneInherit1 send{0}", msg);
65         }
66     }
67 
68     /// <summary>
69     /// 导出
70     /// </summary>
71     [Export("lyb", typeof(DemoOneInterface))]
72     [ExportMetadata("Depict", "2")]
73     public class DemoOneInherit2 : DemoOneInterface
74     {
75         public void Send(string msg)
76         {
77             Console.WriteLine("DemoOneInherit2 send{0}", msg);
78         }
79     }
80     /// <summary>
81     /// 定义 Metadata
82     /// </summary>
83     public interface DemoOneInterfaceDepict
84     {
85         string Depict { get; }
86     }
87 }