ISpMMSysAudio::SetDeviceId (SAPI 5.3)

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Microsoft Speech API 5.3

ISpMMSysAudio::SetDeviceId

ISpMMSysAudio::SetDeviceId sets the multimedia device ID.

  
    HRESULT SetDeviceId(
   UINT   uDeviceId
);

Parameters

  • uDeviceId
    [in] The device ID of the device to set.

Return values

Value
S_OK
SPERR_DEVICE_BUSY
SPERR_ALREADY_INITIALIZED
E_INVALIDARG

Remarks

This method works only on audio objects that were not created using an object token, and only when the object is in the SPAS_CLOSED state. This method should not be used in normal application development. SAPI provides tokens for all the available sound devices in a computer and these can be used to create an initialized SpMMSysAudio object. This method is available for non-standard multimedia audio devices. See the Simple Telephony sample for an example of when this method is useful.

Example

The following code snippet illustrates the use of ISpMMSysAudio::SetDeviceId.

  
// Declare local identifiers:
HRESULT                   hr = S_OK;
CComPtr<ISpMMSysAudio>    cpMMSysAudio;
UINT                      ALTERNATE_MM_DEVICE = 1;
	
// Create the multimedia output object.
hr = cpMMSysAudio.CoCreateInstance(CLSID_SpMMAudioOut);

if (SUCCEEDED (hr))
{
   // Set the output device to an alternate multimedia
   // device (for example, the modem).
   hr = cpMMSysAudio->SetDeviceId(ALTERNATE_MM_DEVICE);
}

if (SUCCEEDED(hr))
{
   // Do stuff here.
}