IMMDeviceCollection::Item

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IMMDeviceCollection::Item

The Item method retrieves a pointer to the specified item in the device collection.

HRESULT Item(
  UINT  nDevice,
  IMMDevice  **ppDevice
);

Parameters

nDevice

[in]  The device number. If the collection contains n devices, the devices are numbered 0 to n – 1.

ppDevice

[out]  Pointer to a pointer variable into which the method writes the address of the IMMDevice interface of the specified item in the device collection. Through this method, the caller obtains a counted reference to the interface. The caller is responsible for releasing the interface, when it is no longer needed, by calling the interface's Release method. If the Item call fails, *ppDevice is NULL.

Return Value

If the method succeeds, it returns S_OK. If it fails, possible return codes include, but are not limited to, the values shown in the following table.

Return code Description
E_POINTER Parameter ppDevice is NULL.
E_INVALIDARG Parameter nDevice is not a valid device number.

Remarks

This method retrieves a pointer to the IMMDevice interface of the specified item in the device collection. Each item in the collection is an endpoint object that represents an audio endpoint device. The caller selects a device from the device collection by specifying the device number. For a collection of n devices, valid device numbers range from 0 to n – 1. To obtain a count of the devices in a collection, call the IMMDeviceCollection::GetCount method.

For a code example that calls the Item method, see Device Properties.

Requirements

Client: Windows Vista

Header: Include Mmdeviceapi.h.

See Also

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