csharp MEF属性ベースのサンプル

Posted 2021-05-12

namespace MEFSamples
{
    using System;
    using System.Linq;

    using System.ComponentModel.Composition;
    using System.ComponentModel.Composition.Hosting;

    class Program
    {
        [Import("upper", typeof(ILog))]
        public ILog Logger { get; set; }

        static void Main(string[] args)
        {
            var catalog = new AggregateCatalog();
            catalog.Catalogs.Add(new AssemblyCatalog(typeof(Program).Assembly));

            var container = new CompositionContainer(catalog);
            var obj = container.GetExportedValue<ILog>("reverse");
            obj.Debug("hello world");

            var me = new Program();
            container.ComposeParts(me);
            me.Logger.Debug("hello world");

            foreach (var item in container.GetExportedValues<ILog>())
            {
                item.Debug("GetExportedValues");
            }
        }
    }

    interface ILog
    {
        void Debug(string message);
    }

    [Export(typeof(ILog))]
    class LogImpl : ILog
    {
        public void Debug(string message)
        {
            Console.WriteLine(message);
        }
    }

    [Export("upper", typeof(ILog))]
    class LogUpperImpl : ILog
    {
        public void Debug(string message)
        {
            Console.WriteLine(message.ToUpper());
        }
    }

    [Export("reverse", typeof(ILog))]
    class LogReverseImpl : ILog
    {
        public void Debug(string message)
        {
            Console.WriteLine(new string(message.Reverse().ToArray()));
        }
    }
}