HRESULT XSpeechSynthesizerEnumerateInstalledVoices(  
         void* context,  
         XSpeechSynthesizerInstalledVoicesCallback* callback  
)  

int Game::CountInstalledVoices()
{
    HRESULT hr = S_OK;
    int* voiceCount = new int();
    // Call XSpeechSynthesizerEnumerateInstalledVoices with a callback function
    // defined as a lambda expression that increments the count of installed voices 
    // each time it's invoked, and outputs information about each voice to the 
    // debugger for display.
    hr = XSpeechSynthesizerEnumerateInstalledVoices(voiceCount,
        [](
            _In_ const XSpeechSynthesizerVoiceInformation* information,
            _In_ void* context
            ) -> bool 
        {
        // Increment and update the count of installed voices.
        int* voiceCount = (int*)context;
        *voiceCount = *voiceCount + 1;
        CopyMemory(context, voiceCount, sizeof(int));

        // Output information about the current installed voice
        // to the debugger for display.
        char buffer[1000];
        int bufferLen;
        bufferLen = sprintf(buffer, "(%s) %s - %s, %s\n",
            information->VoiceId,
            information->Description,
            information->Gender == XSpeechSynthesizerVoiceGender::Male ? "Male" : "Female",
            information->Language);
        OutputDebugStringA(buffer);
      
        // Continue iterating through installed voices.
        // If this was set to false, the calling function would stop
        // enumerating installed voices.
        return true;
        }
    );

    // Return the count of installed voices.
    return *voiceCount;
}