Load Assembly in New AppDomain without loading it in Parent AppDomain

Question

I am attempting to load a dll into a console app and then unload it and delete the file completely. The problem I am having is that the act of loading the dll in its own AppDomain creates a reference in the Parent AppDomain thus not allowing me to destroy the dll file unless I totally shut down the program. Any thoughts on making this code work?

string fileLocation = @"C:\Collector.dll";
AppDomain domain = AppDomain.CreateDomain(fileLocation);
domain.Load(@"Services.Collector");
AppDomain.Unload(domain);

BTW I have also tried this code with no luck either

string fileLocation = @"C:\Collector.dll";
byte[] assemblyFileBuffer = File.ReadAllBytes(fileLocation);

AppDomainSetup domainSetup = new AppDomainSetup();
domainSetup.ApplicationBase = Environment.CurrentDirectory;
domainSetup.ShadowCopyFiles = "true";
domainSetup.CachePath = Environment.CurrentDirectory;
AppDomain tempAppDomain = AppDomain.CreateDomain("Services.Collector", AppDomain.CurrentDomain.Evidence, domainSetup);

//Load up the temp assembly and do stuff 
Assembly projectAssembly = tempAppDomain.Load(assemblyFileBuffer);

//Then I'm trying to clean up 
AppDomain.Unload(tempAppDomain);
tempAppDomain = null;
File.Delete(fileLocation); 

Quietism

Answer 1

OK so I solved my own issue here. Apparently if you call AppDomain.Load it will register it with your parent AppDomain. So simply enough the answer is not to reference it at all. This is the link to a site that shows how to set this up properly.

https://bookie.io/bmark/readable/9503538d6bab80

Quietism

added new link to answer – Littoral

the new link is dead now too – Collar

Links are all dead – Lashundalasker

Answer 2

This should be easy enough:

namespace Parent {
  public class Constants
  {
    // adjust
    public const string LIB_PATH = @"C:\Collector.dll";
  }

  public interface ILoader
  {
    string Execute();
  }

  public class Loader : MarshalByRefObject, ILoader
  {
    public string Execute()
    {
        var assembly = Assembly.LoadFile(Constants.LIB_PATH);
        return assembly.FullName;
    }
  }

  class Program
  {
    static void Main(string[] args)
    {
      var domain = AppDomain.CreateDomain("child");
      var loader = (ILoader)domain.CreateInstanceAndUnwrap(typeof(Loader).Assembly.FullName, typeof(Loader).FullName);
      Console.Out.WriteLine(loader.Execute());
      AppDomain.Unload(domain);
      File.Delete(Constants.LIB_PATH);
    }
  }
}

Evolution

Does not work. I get an unauthorized access exception when i try to delete the file. Did you test your code? – Reichert

@WolfgangRoth - it does work for me. if you're having an specific issue I suggest you ask a new question. – Evolution

I solved my problem: in fact the visual studio debugger connects itself to the assembly while debugging, and it doesnt disconnect any more. But when i run without debugger or when i first load the assembly file into a byte array, everything works fine... – Reichert