IltmmAudioFormats::get_Count Example for C>
// Having an IltmmCapture Interface, pCap:
L_MULTIMEDIATEX_API void IltmmAudioFormats_get_Count_Example (IltmmCapture* pCapture) { IltmmAudioFormats *pAudioFormats; IltmmAudioFormat *pAudioFormat; long lCount; long lFreq, lBits, lChannels; long lFoundAt; long lSelection; VARIANT_BOOL bSelected; int i; // get the audio formats collection: IltmmCapture_get_AudioCaptureFormats(pCapture, &pAudioFormats); IltmmAudioFormats_get_Count(pAudioFormats, &lCount); for( i=0; i<lCount; i++ ) { // get the item at index I IltmmAudioFormats_Item(pAudioFormats, i, &pAudioFormat); // do something with this item, like viewing its information: IltmmAudioFormat_get_SampleFrequency(pAudioFormat, &lFreq); IltmmAudioFormat_get_BitsPerSample(pAudioFormat, &lBits); IltmmAudioFormat_get_Channels(pAudioFormat, &lChannels); IltmmAudioFormat_get_Selected(pAudioFormat, &bSelected); // view information � // you may select the format if it matches some criteria: if( lFreq == 8000 && lBits == 8 && lChannels == 1 ) IltmmAudioFormat_put_Selected(pAudioFormat, VARIANT_TRUE); // free the item IUnknown_Release(pAudioFormat); } // you might use the Find method to search for a specific format: IltmmAudioFormats_Find(pAudioFormats, 16000, 16, 2, &lFoundAt); if( lFoundAt != -1 ) { // do something with it: // check if it is already selected, and if not, select it: IltmmAudioFormats_get_Selection(pAudioFormats, &lSelection); if( lSelection != lFoundAt ) { IltmmAudioFormats_put_Selection(pAudioFormats, lFoundAt); } } // free the audio formats collection IUnknown_Release(pAudioFormats); }