Ninject，将构造函数参数传递给内核 [英] Ninject, passing constructor argument to the kernel

问题描述

这里是我的问题：
我想在每次从内核请求一个实例时将其中的一个值传递给构造函数。我在下面写了一些代码来说明问题。测试是不是失败，所以我想这是可行的，但它看起来很丑陋。有没有更好的，更清洁的方式来完成这个与Ninject？还是应该重新考虑我的设计？

  [TestFixture] 
 public class Sandbox 
 {
 [Test ] 
 public void Run_Forrest_Run（）
 {
 using（var kernel = new StandardKernel（new Module（）））
 {
 var connection = new Connection NewGuid（）。ToString（））; 
 var downloader = kernel.Get< IDownloader>（new IParameter [] {new Parameter（connection，connection，false）}）; 
 
 Assert.That（downloader.Connection.Info，Is.EqualTo（connection.Info））; 
} 
} 
 
 public class Downloader：IDownloader 
 {
 public Downloader（连接连接，ILogger记录器）
 {
连接=连接; 
 Logger = logger; 
} 
 
 public Connection Connection {get;私人集} 
 
 public void Download（）
 {
 Logger.Log（Downloading ...）; 
} 
 
 public ILogger Logger {get;私人集} 
} 
 
 public interface IDownloader 
 {
 Connection Connection {get; } 
 void Download（）; 
} 
 
 public class ConsoleLogger：ILogger 
 {
 public void日志（字符串消息）
 {
 Console.Out.WriteLine ）; 
} 
} 
 
 public interface ILogger 
 {
 void Log（string message）; 
} 
 
 public class Connection 
 {
 public Connection（string info）
 {
 Info = info; 
} 
 
 public string Info {get;私人集} 
} 
 
 public class Module：NinjectModule 
 {
 public override void Load（）
 {
 Bind< ILogger>至< ConsoleLogger>（）; 
 
 Bind< IDownloader>（）。To< Downloader>（）
 .WithConstructorArgument（connection，context => 
 {
 var p = context。 Parameters.First（x => x.Name ==connection）; 
 return p.GetValue（context，null）; 
}）; 
} 
} 
} 
  

解决方案>

如果您在解析 IDownloader 时总是想指定 Connection ，那么我认为 ConstructorArgument （这是一个 IParameter ）是您要查找的：

  [test] 
 public void Run_Forrest_Run（）
 {
 using（var kernel = new StandardKernel（new Module（）））
 { 
 var connection = new Connection（Guid.NewGuid（）。ToString（））; 
 var downloader = kernel.Get< IDownloader>（new [] {
 new ConstructorArgument（connection，connection）}）; 
 
 Assert.That（downloader.Connection.Info，Is.EqualTo（connection.Info））; 
} 
} 
 
 public class Module：NinjectModule 
 {
 public override void Load（）
 {
 Bind< ILogger> ;（）。To< ConsoleLogger>（）; 
 Bind< IDownloader>（）。To< Downloader>（）; 
} 
} 
  

Here is my problem: I want to pass in one of the values to the constructor every time I request an instance form the kernel. I written some code below to illustrate the problem. The test is not failing so I guess that this works, but it does look pretty ugly. Is there a better, cleaner way to accomplish this with Ninject? Or should I rethink my design? All suggestions are appreciated.

[TestFixture]
public class Sandbox
{
    [Test]
    public void Run_Forrest_Run()
    {
        using (var kernel = new StandardKernel(new Module()))
        {
            var connection = new Connection(Guid.NewGuid().ToString());
            var downloader = kernel.Get<IDownloader>(new IParameter[] { new Parameter("connection", connection, false) });

            Assert.That(downloader.Connection.Info, Is.EqualTo(connection.Info));
        }
    }

    public class Downloader : IDownloader
    {
        public Downloader(Connection connection, ILogger logger)
        {
            Connection = connection;
            Logger = logger;
        }

        public Connection Connection { get; private set; }

        public void Download()
        {
            Logger.Log("Downloading...");
        }

        public ILogger Logger { get; private set; }
    }

    public interface IDownloader
    {
        Connection Connection { get; }
        void Download();
    }

    public class ConsoleLogger : ILogger
    {
        public void Log(string message)
        {
            Console.Out.WriteLine(message);
        }
    }

    public interface ILogger
    {
        void Log(string message);
    }

    public class Connection
    {
        public Connection(string info)
        {
            Info = info;
        }

        public string Info { get; private set; }
    }

    public class Module : NinjectModule
    {
        public override void Load()
        {
            Bind<ILogger>().To<ConsoleLogger>();

            Bind<IDownloader>().To<Downloader>()
                .WithConstructorArgument("connection", context =>
                {
                    var p = context.Parameters.First(x => x.Name == "connection");
                    return p.GetValue(context, null);
                });
            }
    }
}

解决方案

If you always want to specify the Connection when resolving a IDownloader then I think the ConstructorArgument (which is a IParameter) is what you are looking for:

[Test]
public void Run_Forrest_Run()
{
    using (var kernel = new StandardKernel(new Module()))
    {
        var connection = new Connection(Guid.NewGuid().ToString());
        var downloader = kernel.Get<IDownloader>(new [] { 
            new ConstructorArgument("connection", connection) });

        Assert.That(downloader.Connection.Info, Is.EqualTo(connection.Info));
    }
}

public class Module : NinjectModule
{
    public override void Load()
    {
        Bind<ILogger>().To<ConsoleLogger>();
        Bind<IDownloader>().To<Downloader>();
    }
}

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