Unity - 为同一个接口注入不同的类

Question

我有一个接口:IFoo
两个实现该接口的类:FooOne和FooTwo
两个类,ClassOne并在构造函数中ClassTwo接收一个IFoo参数.

我如何配置统一以便ClassOne接收一个FooOne实例并只ClassTwo接收FooTwo一个容器？

我不能在运行时这样做,所以它必须在配置文件中.

Answer 1

看看Unity文档.

对于一个更可读的配置文件,你应该定义类型别名IFoo,FooOne,FooTwo,ClassOne和ClassTwo.然后,您需要将映射注册IFoo到您的实现.您需要name为映射设置a .对于IFoo您需要注册的消费者InjectionConstructor.

你的配置看起来像这样:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection,
      Microsoft.Practices.Unity.Configuration"/>
  </configSections>
  <unity xmlns="http://schemas.microsoft.com/practices/2010/unity">
    <alias alias="IFoo" type="UnityConfigFile.IFoo, UnityConfigFile" />
    <alias alias="FooOne" type="UnityConfigFile.FooOne, UnityConfigFile" />
    <alias alias="FooTwo" type="UnityConfigFile.FooTwo, UnityConfigFile" />
    <alias alias="ClassOne" type="UnityConfigFile.ClassOne, UnityConfigFile" />
    <alias alias="ClassTwo" type="UnityConfigFile.ClassTwo, UnityConfigFile" />
    <container>
      <register type="IFoo" name="1" mapTo="FooOne" />
      <register type="IFoo" name="2" mapTo="FooTwo" />
      <register type="ClassOne" mapTo="ClassOne">
        <constructor>
          <param name="foo">
            <dependency type="IFoo" name="1" />
          </param>
        </constructor>
      </register>
      <register type="ClassTwo" mapTo="ClassTwo">
        <constructor>
          <param name="foo">
            <dependency type="IFoo" name="2" />
          </param>
        </constructor>
      </register>
    </container>
  </unity>
</configuration>

这是相应的测试,显示它是如何工作的.

UnityConfigurationSection config =
  (UnityConfigurationSection) ConfigurationManager.GetSection("unity");
IUnityContainer container = new UnityContainer();
container.LoadConfiguration(config);
ClassTwo two = container.Resolve<ClassTwo>();
Assert.IsInstanceOfType(two.Foo, typeof(FooTwo));

更新

在运行时,您可以这样做

IUnityContainer container = new UnityContainer();
container.RegisterType<IFoo, FooOne>("One");
container.RegisterType<IFoo, FooTwo>("Two");
container.RegisterType<ClassOne>(new InjectionConstructor(
  new ResolvedParameter<IFoo>("One")));
container.RegisterType<ClassTwo>(new InjectionConstructor(
  new ResolvedParameter<IFoo>("Two")));

Answer 2

您需要为他们提供注册名称才能执行此操作：

// Create an instance of a service you want to use. Alternatively, this
// may have been created by another process and passed to your application
LoggingService myLoggingService = new LoggingService();

// Register the existing object instance with the container
container.RegisterInstance<IMyService>("Logging", myLoggingService);

// Register a mapping for another service your application will use
container.RegisterType<IMyService, myDataService>("DataService");

// When required, retrieve an instance of these services
IMyService theDataService = container.Resolve<IMyService>("DataService");
IMyService theLoggingService = container.Resolve<IMyService>("Logging");

取自使用 Unity 解析类型的实例