MicrophoneSetup函数调用

释放函数Destroy被类的析构函数调用，释放了类所引用的所有接口：

void CSpeechRecognition::Destroy()

{

if (m_cpDictationGrammar)

m_cpDictationGrammar.Release();

if (m_cpRecoCtxt)

m_cpRecoCtxt.Release();

if (m_cpRecoEngine)

m_cpRecoEngine.Release();

CoUninitialize();

}

函数Start和Stop用来控制开始和停止接受及识别语音，它们通过调用引擎接口的SetRecoState方法来实现：

BOOL CSpeechRecognition::Start()

{

if (m_bOnDictation)

return TRUE;

HRESULT hr = m_cpRecoEngine->SetRecoState( SPRST_ACTIVE );

if (FAILED(hr))

return FALSE;

m_bOnDictation = TRUE;

return TRUE;

}

BOOL CSpeechRecognition::Stop()

{

if (! m_bOnDictation)

return TRUE;

HRESULT hr = m_cpRecoEngine->SetRecoState( SPRST_INACTIVE )