IltmmAudioFormats::get_Count Example for C++

// Having an IltmmCapture Interface, pCap:

IltmmAudioFormats *pAudioFormats;
IltmmAudioFormat *pAudioFormat;
long   lCount;
long lFreq, lBits, lChannels;
long lFoundAt;
long lSelection;
VARIANT_BOOL bSelected;

// get the audio formats collection:
pCap->get_AudioCaptureFormats(&pAudioFormats);
pAudioFormats->get_Count(&lCount);

for( i=0; i<lCount; i++ )
{
   // get the item at index I
   pAudioFormats->Item(i, &pAudioFormat);
  
   // do something with this item, like viewing its information:
   pAudioFormat->get_SampleFrequency(&lFreq);
   pAudioFormat->get_BitsPerSample(&lBits);
   pAudioFormat->get_Channels(&lChannels);
   pAudioFormat->get_Selected(&bSelected);

   // view information …

   // you may select the format if it matches some criteria:
   if( lFreq == 8000 && lBits == 8 && lChannels == 1 )
         pAudioFormat->put_Selected(VARIANT_TRUE);

   // free the item
   pAudioFormat->Release();
}

// you might use the Find method to search for a specific format:
pAudioFormats->Find(16000, 16, 2, &lFoundAt);
If( lFoundAt != -1 )
{
   // do something with it:
   // check if it is already selected, and if not, select it:
   pAudioFormats->get_Selection(&lSelection);
   If( lSelection != lFoundAt )
   {
      pAudioFormats->put_Selection(lFoundAt);
   }
}

// free the audio formats collection
 pAudioFormats->Release();