middleweight-reflection

MiddleweightReflection is a .Net library that wraps System.Reflection.Metadata. SRM is a very simple, lightweight library for reading ECMA 335 .Net assemblies and Windows WinMD files. MiddleweightReflection wraps that to make things easier, though a little heavier.

Usage

To use the library, load some metadata files into a Context, and then you can enumerate the assemblies, their types, and their members (including attributes). If it can't find a referenced assembly you can answer a callback to provide its location. If you don't, it automatically creates a fake assembly with fake types.

There's a basic example in the unit test.

NuGet: https://www.nuget.org/packages/mikehillberg.middleweightreflection

Note that unless you load .Net assemblies, assemblies such as System will be faked. The faking works pretty well, but for example you won't be able to determine the T in EventHandler<T>, because System.EventHandler~1 will be faked.

But you can supply extra assemblies using the AssemblyPathFromName callback. For example, handling a few interesting cases in .Net Framework:

var loadContext = new MrLoadContext();
loadContext.AssemblyPathFromName = (requestedName) =>
{
    string location = null;

    if (requestedName == "mscorlib")
    {
        location = (typeof(string).Assembly).Location;
    }
    else if (requestedName == "System")
    {
        location = typeof(NetTcpStyleUriParser).Assembly.Location;
    }
    else if (requestedName == "System.Runtime")
    {
        var mscorlib = (typeof(string).Assembly).Location;
        mscorlib = mscorlib.Substring(0, mscorlib.LastIndexOf('\\'));
        location = $@"{mscorlib}\System.Runtime.dll";
    }
    else
    {
        Debug.WriteLine($"Faking assembly {requestedName}");
    }

    return location;
};

Versions

1.1.3 Don't try to guess at the location of .Net assemblies like mscorlib; fake them by default, or caller can provide them.

1.1.2 Added an overload to LoadAssemblyFromBytes to take a path (which is just returned from Assembly.Location)

Issues

There are some more advanced metadata features not covered yet, but the most notable are:

• Assembly attributes
• Full support for fully qualified assembly names