Custom config section: Could not load file or assembly

Question

I\'m having a very hard time trying to access a custom configuration section in my config file.

The config file is being read from a .dll that is loaded as a plug-in

Answer 1

To expand on AJ's excellent answer, here is a custom class to assist with the overhead of registering and removing the global event.

public sealed class AddinCustomConfigResolveHelper : IDisposable
{
    public AddinCustomConfigResolveHelper(
        Assembly addinAssemblyContainingConfigSectionDefinition)
    {
        Contract.Assert(addinAssemblyContainingConfigSectionDefinition != null);

        this.AddinAssemblyContainingConfigSectionDefinition =
            addinAssemblyContainingConfigSectionDefinition;

        AppDomain.CurrentDomain.AssemblyResolve +=
            this.ConfigResolveEventHandler;
    }

    ~AddinCustomConfigResolveHelper()
    {
        this.Dispose(false);
    }

    public void Dispose()
    {
        this.Dispose(true);
        GC.SuppressFinalize(this);
    }

    private void Dispose(bool isDisposing)
    {
        AppDomain.CurrentDomain.AssemblyResolve -= this.ConfigResolveEventHandler;
    }

    private Assembly AddinAssemblyContainingConfigSectionDefinition { get; set; }

    private Assembly ConfigResolveEventHandler(object sender, ResolveEventArgs args)
    {
        // often the name provided is partial...this will match full or partial naming
        if (this.AddinAssemblyContainingConfigSectionDefinition.FullName.Contains(args.Name))
        {
            return this.AddinAssemblyContainingConfigSectionDefinition;
        }

        return null;
    }
}

I would suggest creating an instance in a using statement, like so:

// you'll need to populate these two variables
var configuration = GetConfiguration();
var assembly = GetAssemblyContainingConfig();

using(new AddinCustomConfigResolveHelper(assembly))
{
    return (MyConfigSection)configuration.GetSection("myConfigSection");
}