如何将依赖项名称作为构造函数参数注入

Dig*_*ift 5 .net c# autofac property-injection

使用Autofac,我可以使用以下代码注册一个类来解析使用属性注入的接口:

builder.RegisterType<Log4NetAdapter>()
       .As<ILogger>()
       .PropertiesAutowired()
       .InstancePerDependency();
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但是,我的Log4NetAdapter类有一个构造函数参数,需要调用类的名称.这样,我可以根据调用类的名称记录事件.

public class Log4NetAdapter : ILogger
{
    private readonly ILog _logger;

    public Log4NetAdapter(string logName)
    {
        _logger = LogManager.GetLogger(logName);
    }

    ...
}
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typeof(dependency).Name如果每个依赖项都有自己的Log4NetAdapter实例,我怎样才能将依赖项的名称(即)注入到属性注入类的构造函数中?

Pet*_*old 4

更新:基于LogInjectionModule示例以及Autofac 如何进行属性注入,我扩展了该模块以执行构造函数和属性注入。

LogManager注意:我已经修复了传递给in 的类型OnComponentPreparing以使用声明类型。这使得例如Resolve<Func<Service>>使用正确的日志类型。

    using System.Linq;
    using log4net;

    public class LogInjectionModule : Module
    {
        protected override void AttachToComponentRegistration(IComponentRegistry registry, IComponentRegistration registration)
        {
            registration.Preparing += OnComponentPreparing;
            registration.Activating += OnComponentActivating;
        }

        private static void OnComponentActivating(object sender, ActivatingEventArgs<object> e)
        {
            InjectLogProperties(e.Context, e.Instance, false);
        }

        private static void OnComponentPreparing(object sender, PreparingEventArgs e)
        {
            e.Parameters = e.Parameters.Union(new[]
                {
                    new ResolvedParameter(
                       (p, i) => p.ParameterType == typeof(ILog),
                       (p, i) => LogManager.GetLogger(p.Member.DeclaringType))
                });
        }

        private static void InjectLogProperties(IComponentContext context, object instance, bool overrideSetValues)
        {
            if (context == null) throw new ArgumentNullException("context");
            if (instance == null) throw new ArgumentNullException("instance");

            var instanceType = instance.GetType();
            var properties = instanceType
                .GetProperties(BindingFlags.Public | BindingFlags.Instance)
                .Where(pi => pi.CanWrite && pi.PropertyType == typeof(ILog));

            foreach (var property in properties)
            {
                if (property.GetIndexParameters().Length != 0)
                    continue;

                var accessors = property.GetAccessors(false);
                if (accessors.Length == 1 && accessors[0].ReturnType != typeof(void))
                    continue;

                if (!overrideSetValues &&
                    accessors.Length == 2 &&
                    (property.GetValue(instance, null) != null))
                    continue;

                ILog propertyValue = LogManager.GetLogger(instanceType);
                property.SetValue(instance, propertyValue, null);
            }
        }
    }
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关于如何使用该模块,这里有一个示例:

public class Service
{
    public Service(ILog log) { ... }
}

var cb = new ContainerBuilder();
cb.RegisterModule<LogInjectionModule>();
cb.RegisterType<Service>();
var c = cb.Build();

var service = c.Resolve<Service>();
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