C# Unity container Ctor injection

Say we have:

class A
{
   ILogger myLog;
   A(ILogger log)
   {
      this.myLog = log;
   }
 开发者_如何学运维...
}

And we have registered the ILogger interface before in the unity container, e.g.

 container.RegisterType<ILogger, SomeLogger>();

And here the SomeLogger class:

class SomeLogger : ILogger
{
   string myString;
   SomeLogger(string test)
   {
     myString = test;
   }
 ...
}

Now, how can unity create an instance of SomeLogger for class A without passing a string to the ctor of SomeLogger? Suppose there is no other ctor for SomeLogger. Where can one specify the parameter(s) for ctor of the mapped SomeLogger type?

---

You can do that in your configuration:

<?xml version="1.0"?>
<configuration>
    <configSections>
        <section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration" />
    </configSections>
    <unity>
        <containers>
            <container>
                <types>
                    <type type="[Namespace].ILogger, [AssemblyName]" mapTo="[Namespace].SomeLogger, [AssemblyName]">
                        <constructor>
                            <param name="test">
                                <value value="MyDesiredValue" />
                            </param>
                        </constructor>
                    </type>
                </types>
            </container>
        </containers>
  </unity>
</configuration>

This also declaratively registers your type, so the

container.RegisterType<ILogger, SomeLogger>();

call is no longer necessary.

-Doug

---

You can do this:

container.RegisterType<ILogger, SomeLogger>(new InjectionConstructor("myStringValue"));

---

you could also do this in the registration code as follows:

UnityContainer.RegisterType<ILogger, SomeLogger>();
UnityContainer.Configure<InjectedMembers>()
              .ConfigureInjectionFor<SomeLogger>(new InjectionConstructor("TestString"));