Castle Windsor - multiple implementation of an interface
Solution 1
The above answers lead me to inline dependencies and the feature service override
Here is the registration code:
container.Register(Component.For<IReport>().ImplementedBy<NortonService>().Named("nortonService"));
container.Register(Component.For<ILogger>().ImplementedBy<FileLogger>());
container.Register(Component.For<ILogger>().ImplementedBy<DatabaseLogger>());
container.Register(
Component.For<IReport>().ImplementedBy<McAfeeService>().Named("mcafeeService")
.DependsOn(Dependency.OnComponent<ILogger, DatabaseLogger>())
);
IReport mcafeescan = container.Resolve<IReport>("mcafeeService");
mcafeescan.LogReport();
IReport nortonscan = container.Resolve<IReport>("nortonService");
nortonscan.LogReport();
Output:
McAfee Scan has Logged data to a database
Norton Scan has Logged data to a file
Solution 2
I had a problem very like this, two implementation of one interface and two implementation of another interface. I wanted to force usage of particular implementations of those interfaces.
My class structure looked like this -
I looked at the naming convention, but didn't really like it. Instead I used the following -
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.Register(
Component.For<IMessageLoader>().ImplementedBy<MessageLoaderDatabase>()
,Component.For<IMessageLoader>().ImplementedBy<MessageLoaderFile>()
,Component.For<IMessageOfTheDayService>().ImplementedBy<MessageOfTheDayServiceDatabase>()
.DependsOn(Dependency.OnComponent<IMessageLoader, MessageLoaderDatabase>())
,Component.For<IMessageOfTheDayService>().ImplementedBy<MessageOfTheDayServiceFile>()
.DependsOn(Dependency.OnComponent<IMessageLoader, MessageLoaderFile>())
,Component.For<MessageOfTheDayController>().LifestyleTransient()
.DependsOn(Dependency.OnComponent<IMessageOfTheDayService, MessageOfTheDayServiceFile>())
);
Full info about this approach is here. In the source code provided with that post I show two other ways of achieving the same result.
Solution 3
If you want to do it at runtime, This can be acheived through IHandlerSelector. Write a class that implements IHandlerSelector. It provides a method SelectHandler which will let you define the condition for binding conditionally at runtime. A Handler in this case is a component in Windsor that participates in instance construction. Refer here for more details.
Solution 4
My answer maybe not the best one, you can use naming method to resolve multi implementation:
container.Register(Component.For(typeof(ILogger))
.ImplementedBy(typeof(FileLogger))
.Named("FileLoggerIoC")
.LifestylePerWebRequest() ,
Component.For(typeof(ILogger))
.ImplementedBy(typeof(DatabaseLogger))
.Named("DatabaseLoggerIoC")
.LifestylePerWebRequest());
In your calling functions, you need to resolve it by name :-
var fileLog = container.Resolve("FileLoggerIoC", typeof(ILogger));
var DbLog = container.Resolve("DatabaseLoggerIoC", typeof(ILogger));
Mine method maybe not the best one as people don't like service locator to get the components, you can use this as temporary solution.
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Chinmay Lokesh
Software Developer with professional experience on the Microsoft Stack.
Updated on May 17, 2020Comments
-
Chinmay Lokesh almost 4 years
While registering components in Castle Windsor, how do we bind specific implementation of an interface to a component that has a dependency on that interface. I know in advance which implementation needs to be used by the component.
For example i created a sample console application based on code from several blogs and tutorials.
Following is the code.
public interface IReport { void LogReport(); } public interface ILogger { string Log(); } public class FileLogger : ILogger { public string Log() { return "Logged data to a file"; } } public class DatabaseLogger : ILogger { public string Log() { return "Logged data to a database"; } } public class McAfeeService : IReport { private readonly ILogger _logger; public McAfeeService(ILogger logger) { this._logger = logger; } public void LogReport() { string getLogResult = this._logger.Log(); Console.WriteLine("McAfee Scan has " + getLogResult); } } public class NortonService : IReport { private readonly ILogger _logger; public NortonService(ILogger logger) { this._logger = logger; } public void LogReport() { string getLogResult = this._logger.Log(); Console.WriteLine("Norton Scan has " + getLogResult); } } class Program { private static IWindsorContainer container; static void Main(string[] args) { // Register components container = new WindsorContainer(); container.Register(Component.For<IReport>().ImplementedBy<NortonService>()); container.Register(Component.For<ILogger>().ImplementedBy<FileLogger>()); IReport service = container.Resolve<IReport>(); service.LogReport(); Console.ReadLine(); } }
I would like NortonService to always use a Filelogger and McAfeeService to use a Database Logger.
In the above program i am unable to bind NortonService to FileLogger.
How to do it?