How to specify a CodeSet for WChar string from a CORBA client

This question is related to another question with which I have been struggling: How to access CORBA interface without IDL or late-bound invoke remoting methods

I'm really stumped on how to get past this error about the CodeSet not being specified. I have been tracing into the IIOP code trying to figure out how the CodeSet can be specified, and it looks like it could be specified with a tagged component associated with the profile. Being unfamiliar with CORBA, I don't know what a tagged component is or what a profile is or how to control them, but I suspect that it may be influenced by creating a portable object interceptor, at which point I could add a tagged CodeSet component to the profile, if that means anything. I'm just going by what I can learn from the IIOP.NET code and Google.

Could someone please help me understand and hopefully control this? If the server is a black box and I need to write a client to call a method that outputs a string, how do I tell IIOP.NET what WChar CodeSet to use so it doesn't give me an error about it being unspecified. I tried OverrideDefaultCharSets from the client, but that didn't seem to have any effect. The IIOP sample code for that function shows it being used on the server side.

Solution

This was a real pain to work out, but I got it:

class MyOrbInitializer : omg.org.PortableInterceptor.ORBInitializer
{
    public void post_init(omg.org.PortableInterceptor.ORBInitInfo info)
    {
        // Nothing to do
    }

    public void pre_init(omg.org.PortableInterceptor.ORBInitInfo info)
    {
        omg.org.IOP.Codec codec = info.codec_factory.create_codec(
            new omg.org.IOP.Encoding(omg.org.IOP.ENCODING_CDR_ENCAPS.ConstVal, 1, 2));
        Program.m_codec = codec;
    }
}


class Program
{
    public static omg.org.IOP.Codec m_codec;

    static void Main(string[] args)
    {
        IOrbServices orb = OrbServices.GetSingleton();
        orb.OverrideDefaultCharSets(CharSet.UTF8, WCharSet.UTF16);
        orb.RegisterPortableInterceptorInitalizer(new MyOrbInitializer());
        orb.CompleteInterceptorRegistration();
...
        MarshalByRefObject objRef = context.resolve(names);
        string origObjData = orb.object_to_string(objRef);
        Ch.Elca.Iiop.CorbaObjRef.Ior iorObj = new Ch.Elca.Iiop.CorbaObjRef.Ior(origObjData);
        CodeSetComponentData cscd = new CodeSetComponentData(
            (int)Ch.Elca.Iiop.Services.CharSet.UTF8,
            new int[] { (int)Ch.Elca.Iiop.Services.CharSet.UTF8 },
            (int)Ch.Elca.Iiop.Services.WCharSet.UTF16,
            new int[] { (int)Ch.Elca.Iiop.Services.WCharSet.UTF16 });
        omg.org.IOP.TaggedComponent codesetcomp = new omg.org.IOP.TaggedComponent(
            omg.org.IOP.TAG_CODE_SETS.ConstVal, m_codec.encode_value(cscd));
        iorObj.Profiles[0].TaggedComponents.AddComponent(codesetcomp);
        string newObjData = iorObj.ToString();
        MarshalByRefObject newObj = (MarshalByRefObject)orb.string_to_object(newObjData);
        ILicenseInfo li = (ILicenseInfo)newObj;
...
    }

Unfortunately in my case the problem remained that the byte ordering was backwards too, so I had to go with an entirely different solution based on just getting bytes back and manually converting them to a string instead of getting string directly.