IDeviceTopology::GetPartById method (devicetopology.h)
The GetPartById method gets a part that is identified by its local ID.
Syntax
HRESULT GetPartById(
[in] UINT nId,
[out] IPart **ppPart
);
Parameters
[in] nId
The part to get. This parameter is the local ID of the part. For more information, see Remarks.
[out] ppPart
Pointer to a pointer variable into which the method writes the address of the IPart interface of the part object that is identified by nId. 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 GetPartById call fails, *ppPart 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 |
|---|---|
|
Parameter nId is not a valid local ID. |
|
Pointer ppPart is NULL. |
Remarks
A local ID is a number that uniquely identifies a part among all the parts in a device topology. The IAudioInputSelector::GetSelection and IAudioOutputSelector::GetSelection methods retrieve the local ID of a connected part. The IAudioInputSelector::SetSelection and IAudioOutputSelector::SetSelection methods select the input or output that is connected to a part that is identified by its local ID. When you have a pointer to a part object, you can call the IPart::GetLocalId method to get the local ID of the part.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows Vista [desktop apps only] |
| Minimum supported server | Windows Server 2008 [desktop apps only] |
| Target Platform | Windows |
| Header | devicetopology.h |
See also
IAudioInputSelector::GetSelection
IAudioInputSelector::SetSelection
IAudioOutputSelector::GetSelection