解决通用的Microsoft.Extensions.Logging.ILogger< T>与Unity一起使用

本文介绍了解决通用的Microsoft.Extensions.Logging.ILogger< T>与Unity一起使用-获取InvalidCastException的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我正在尝试在Unity(版本4)中注册通用ILogger(来自Microsoft.Extensions.Logging，而不是来自Serilog).

I am trying to register a generic ILogger (from Microsoft.Extensions.Logging, not from Serilog) in Unity (version 4).

我有以下课程:

public class MyClass { private readonly Microsoft.Extensions.Logging.ILogger<MyClass> _logger; public MyClass(Microsoft.Extensions.Logging.ILogger<MyClass> logger) { _logger = logger; } }

以及以下Unity注册和测试:

And the following Unity registrations and test:

// Arrange IUnityContainer container = new UnityContainer(); // provider from Serilog.Extensions.Logging nuget package var provider = new Serilog.Extensions.Logging.SerilogLoggerProvider(); container.RegisterType(typeof(Microsoft.Extensions.Logging.ILogger<>), new InjectionFactory((ctr, type, name) => { var loggerType = type.GetGenericArguments()[0].FullName; Microsoft.Extensions.Logging.ILogger logger = provider.CreateLogger(loggerType); return logger; })); container.RegisterType<MyClass, MyClass>(); // just for demo purpose. // Assert container.Resolve<MyClass>();

对我来说这似乎还可以，很糟糕，解决时我遇到了以下错误:

This seems OK to me, too bad I am having the following error when resolving:

异常是:InvalidCastException-无法将类型为'Serilog.Extensions.Logging.SerilogLogger'的对象转换为类型为'Microsoft.Extensions.Logging.ILogger`1 [MyNamespace.MyClass]'.

Exception is: InvalidCastException - Unable to cast object of type 'Serilog.Extensions.Logging.SerilogLogger' to type 'Microsoft.Extensions.Logging.ILogger`1[MyNamespace.MyClass]'.

如何解决此问题?

完全例外:

Microsoft.Practices.Unity.ResolutionFailedException:依赖关系的解析失败，请键入="MyNamespace.MyClass"，名称=(none)". 发生以下异常:解析构造函数MyNamespace.MyClass(Microsoft.Extensions.Logging.ILogger 1[[MyNamespace.MyClass, MyNamespace.Infra.UnitTests, Version=1.0.0.0, Culture=neutral, PublicKeyToken=edbaf8e9a324553f]] logger). Exception is: InvalidCastException - Unable to cast object of type 'Serilog.Extensions.Logging.SerilogLogger' to type 'Microsoft.Extensions.Logging.ILogger 1 [MyNamespace.MyClass]'的参数记录器".

Microsoft.Practices.Unity.ResolutionFailedException: Resolution of the dependency failed, type = "MyNamespace.MyClass", name = "(none)". Exception occurred while: Resolving parameter "logger" of constructor MyNamespace.MyClass(Microsoft.Extensions.Logging.ILogger1[[MyNamespace.MyClass, MyNamespace.Infra.UnitTests, Version=1.0.0.0, Culture=neutral, PublicKeyToken=edbaf8e9a324553f]] logger). Exception is: InvalidCastException - Unable to cast object of type 'Serilog.Extensions.Logging.SerilogLogger' to type 'Microsoft.Extensions.Logging.ILogger1[MyNamespace.MyClass]'.

更新

使用Microsoft.Extensions.DependencyInjection时，此方法有效:

Update

when using Microsoft.Extensions.DependencyInjection, this works:

// Arrange var serviceCollection = new Microsoft.Extensions.DependencyInjection.ServiceCollection() .AddLogging(builder => builder.AddSerilog()) .AddTransient<MyClass, MyClass>(); var serviceProvider = serviceCollection.BuildServiceProvider(); // Assert serviceProvider.GetService<MyClass>();

所以我尝试使用Unity而不是Microsoft.Extensions.DependencyInjection

So I try to get this working with Unity instead of Microsoft.Extensions.DependencyInjection

不幸的是，Unity没有AddSerilog，我已经绑定到Unity

Unfortunately there is no AddSerilog for Unity and I'm bound to Unity

推荐答案

我借助MakeGenericMethod和辅助方法解决了此问题:

I resolved this with the help of MakeGenericMethod and a helper method:

private static ILogger<T> CreateLogger<T>(ILoggerFactory factory) { return new Logger<T>(factory); }

最后的代码(没有反射缓存等):

And the final code (without reflection caching etc):

// Arrange IUnityContainer container = new UnityContainer(); var logfactory = new LoggerFactory(); var provider = new Serilog.Extensions.Logging.SerilogLoggerProvider(); logfactory.AddProvider(provider); container.RegisterType(typeof(Microsoft.Extensions.Logging.ILogger<>), new InjectionFactory((ctr, type, name) => { var loggerType = type.GetGenericArguments()[0]; var myType = this.GetType(); var createLoggerMethod1 = myType.GetMethod(nameof(CreateLogger),BindingFlags.Static | BindingFlags.NonPublic); var createLoggerMethod = createLoggerMethod1.MakeGenericMethod(loggerType); var logger = createLoggerMethod.Invoke(this, new object[] {logfactory}); return logger; })); container.RegisterType<MyClass, MyClass>(); // Assert container.Resolve<MyClass>();