Speech Recognition does not trigger EventHandler in C++/CLI DLL - events

Question

I have a TS3 plugin in creation right here, which uses
System::Speech::Recognition for its SpeechRecognitinEngine. Now, I create an EventHandler for the SpeechRecognized event.
Well, my logging (and the actions of the plugin - None) tell me, that the Event is actually never triggered, even if you start and stop talking with the (somewhat) valid (parts of the) grammar.
I have no idea why this is. It happens in a DLL written in C++ CLI.
Now, my theory was that DLLs do not support event handerls... Might that be possible?
void recogn_speech() {
uint64 schid = ts3Functions.getCurrentServerConnectionHandlerID();
SpeechRecognitionEngine^ recognizer = gcnew SpeechRecognitionEngine();
System::Speech::Recognition::Grammar^ g = assembleGrammar();
recognizer->LoadGrammar(g);
recognizer->SetInputToDefaultAudioDevice();
char pluginPath[PATH_BUFSIZE];
ts3Functions.getPluginPath(pluginPath, PATH_BUFSIZE, pluginID);
String^ a = gcnew String(pluginPath);
a = a + "vctest_cpp_ts3\\signal_vc_start.wav";
char* newPath = (char*)(void*)Marshal::StringToHGlobalAnsi(a);
ts3Functions.playWaveFile(schid, newPath);
Marshal::FreeHGlobal((IntPtr)newPath);
recognizer->SpeechRecognized +=
gcnew EventHandler<SpeechRecognizedEventArgs^>(this, &tsapi::sre_SpeechRecognized);
}
void sre_SpeechRecognized(Object^ sender, SpeechRecognizedEventArgs^ e)
{
uint64 schid = ts3Functions.getCurrentServerConnectionHandlerID();
String^ recognRes = e->Result->Text->ToString();
interpretCommand(recognRes);
}
Full Sourcecode on
GitHub

Answer 1

Your event handler looks correct. There's no issue with having events & event handlers across DLLs: It's all managed code, the DLL boundary doesn't matter here.
However, there is one possible issue:
void recogn_speech() {
...
SpeechRecognitionEngine^ recognizer = gcnew SpeechRecognitionEngine();
...
}
You might want to save your SpeechRecognitionEngine object somewhere so it doesn't get garbage collected.
Also, you may want to switch to the more C++-style of having class definitions in .h files, and implementations in .cpp files. As your code gets more complex and the classes need to refer to each other, having everything in one file will start to become an issue.