You'll need to add the following to the app.config so that plug-in DLL's will be in the probing path.
<runtime> <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1"> <probing privatePath=".\Plugin" /> </assemblyBinding> </runtime>
This is where the plug in DLLs will be saved at runtime. In your composition root the plug-ins assemblies will need to be loaded into the AppDomain so the IoC container can find the plug in types.
public class AssemblyMetadata
{
public string FileName { get; set; }
public string Path { get; set; }
}
public class PlugInAssemblyLoader
{
public void DiscoverAssembliesInPlugInFolder(string path, Predicate<AssemblyMetadata> assemblyFilter)
{
if (!File.Exists(path))
{
return;
}
var assemblies = Directory.GetFiles(path).Where(f => Path.GetExtension(f) == ".dll").Select(f => new AssemblyMetadata {FileName = Path.GetFileName(f), Path = f});
assemblies = assemblies.Where(a => assemblyFilter(a));
foreach (var assemblyFile in assemblies)
{
Assembly.LoadFile(assemblyFile.Path);
}
LoadAssembliesIntoAppDomain(discoveredAssemblies);
}
}
public class CompositionRoot
{
public void MapTypes()
{
// Other type registrations with your IoC container...omitted...
// Load any (if any) plugin libraries into memory
string plugInLibraryLocation = AppDomain.CurrentDomain.BaseDirectory + @"\Plugin"; // Or look up from app.config etc
new PlugInAssemblyLoader().DiscoverAssembliesInPlugInFolder(plugInLibraryLocation, metadata => metadata.FileName.StartsWith("MyCompany"));
// Be sure to trigger loading app.config registrations for your IoC container. This is where your plugins will be registered.
// Plugin types could be replacement for standard types necessary in the application, or they could be optional plugins (ie additional filters e
}
}
