Example of XSockets.Pluginframework - The idea here is that we can get hold of plugins without any configuration. By having export/import attributes on our interfaces we only have to implement a interface to get the plugin functionality. So we only need a reference to the interfaces and the pluginframework.... The actual plugins may be assemblie…

ExportImportInterfaces.dll

//The interfaces export the correct inteface, but can also import interfaces on properties.
//The implementing class does not need to do any imports/exports. It will be taken care of....
[Export(typeof(IZoo))]
public interface IZoo
{
    [ImportMany(typeof(IAnimal))]
    IList<IAnimal> Animals { get; set; }
}

[Export(typeof(IAnimal))]
public interface IAnimal
{
    string Say();
}

Plugins.dll

//Note, this assembly is not referenced by any other project...

//Early Interface Binding
//Note that the plugins does not know of anything but the interfaces assembly.
//They will still be exported since the interfaces has import/export attributes.
public class Lion : IAnimal
{
    public string Say()
    {
        return "Grr";
    }
}

public class Donkey : IAnimal
{
    public string Say()
    {
        return "Yeeehaaa";
    }
}

public class Zoo : IZoo
{        
    public IList<IAnimal> Animals { get; set; }
}

Program.cs

//Note: The program will only know of the ImportExportInterfaces.dll at compile-time... 
//The plugins (Plugins.dll and others) will be located dynamically by configuration or even a filesystemwatcher etc in runtime

//Accuire one instance of the IZoo interface... If we hade several zoo´s (or were unsure of it) we could use GetExports<T>
var zoo = Composable.GetExport<IZoo>();

//The Zoo will now automatically contain a list of the exported animals Donkey and Lion.
foreach (var animal in zoo.Animals)
{
    Console.WriteLine(animal.Say());
}

//Output:
Grr
Yeeehaaa