> ## Documentation Index
> Fetch the complete documentation index at: https://devdocs.xbox.com/llms.txt
> Use this file to discover all available pages before exploring further.

# CreateCaptureAudioStateMonitor

> CreateCaptureAudioStateMonitor

# CreateCaptureAudioStateMonitor

\[部分信息涉及预发布产品,在其正式发布之前可能会发生重大更改。对于此处提供的信息,Microsoft 不作任何明示或默示的担保。]

创建 [IAudioStateMonitor](/reference/audio/audiostatemonitor/interfaces/iaudiostatemonitor) 的新实例,用于监视所有音频捕获流的音频级别。

## Syntax

```cpp theme={null}
HRESULT WINAPI CreateCaptureAudioStateMonitor(
  _Out_ IAudioStateMonitor **audioStateMonitor
);
```

### Parameters

*audioStateMonitor* \_Out\_
Type: IAudioStateMonitor\*\*

此输出参数将填充所创建的 `IAudioStateMonitor` 对象。

### Return value

Type: HRESULT

如果方法成功,则返回 `S\_OK`。

## Remarks

这是用于创建并返回 `AudioStateMonitor` 实例的其中一个函数。

对于捕获流和呈现流,各有四个变体,用于确定进程是否可以针对给定角色执行以下操作之一:

* 捕获或呈现任意类别的任意音频
* 捕获或呈现特定类别的音频
* 将特定类别的音频捕获或呈现到特定终结点。\
  终结点可以通过 `MMDevice` ID(使用 `IMMDevice::GetId()` 获取)指定,也可以通过其 `SWD` ID(使用 `Windows.Devices.Enumeration` 或 `Windows.Media.Devices.MediaDevice` 获取)指定
* 将特定类别的音频捕获或呈现到默认终结点

请思考以下场景:游戏仅在确定操作系统策略不会将音频静音时,才启用其游戏内 GameChat 功能。为此,游戏在默认通信终结点上为 [AudioCategory\_GameChat](https://learn.microsoft.com/windows/win32/api/audiosessiontypes/ne-audiosessiontypes-audio_stream_category) 流类别注册 SoundLevel 通知。

如果此类别的 SoundLevel 被设置为 “Muted”,游戏将停止其 GameChat 会话;如果 SoundLevel 是其他任何值,游戏将选择启用其 GameChat 流。

以下代码示例演示了游戏如何为此场景创建适当的 `IAudioStateMonitor` 对象。

```cpp theme={null}
HRESULT RegisterForSoundLevelChanges() 
{ 
HRESULT hr = S_OK; 

// Create a new AudioStateMonitor for the GameChat category, if needed, and 
// register for callbacks. 
if (m_audioStateMonitor == nullptr) 
{ 
hr = CreateCaptureAudioStateMonitorForCategoryAndDeviceRole( 
AudioCategory_GameChat, ERole::eCommunications, 
g_audioStateMonitor.put()); 
if (SUCCEEDED(hr)) 
{ 
// Optional "context" parameter is not used in this example, 
// and is set to nullptr. 
hr = g_audioStateMonitor->RegisterCallback(OnAudioStateMonitorCallback, nullptr, &m_registration); 
} 
} 

if (FAILED(hr)) 
{ 
// g_audioStateMonitor is a smart pointer, so if an IAudioStateMonitor was 
// allocated, setting the smart pointer to null invokes the Release method 
// which will decrement its usage count and ensure that the object is properly 
// destroyed. 
g_audioStateMonitor = nullptr; 
} 
return hr; 
} 
```

## Requirements

**头文件:** Audiostatemonitorapi.h

**库:** Windows.Media.MediaControl.lib

**支持的平台:** Windows、XBOX One 系列主机和 XBOX Series 主机

## Conceptual documentation

* [音频概述](/build/console-features/audio/overviews/audio)

## See also

[AUDIO\_STREAM\_CATEGORY](https://learn.microsoft.com/windows/win32/api/audiosessiontypes/ne-audiosessiontypes-audio_stream_category)

[关于 WASAPI](https://learn.microsoft.com/windows/desktop/CoreAudio/wasapi)

[WASAPI](/build/console-features/audio/overviews/wasapi-overview)


## Related topics

- [IAudioStateMonitor 接口](/zh-CN/reference/audio/audiostatemonitor/interfaces/iaudiostatemonitor.md)
- [AudioStateMonitor](/zh-CN/reference/audio/audiostatemonitor/audiostatemonitor_members.md)
- [音频概述](/zh-CN/build/console-features/audio/overviews/audio.md)
- [CreateCaptureAudioStateMonitorForCategory](/zh-CN/reference/audio/audiostatemonitor/functions/createcaptureaudiostatemonitorforcategory.md)
- [CreateCaptureAudioStateMonitorForCategoryAndDeviceId](/zh-CN/reference/audio/audiostatemonitor/functions/createcaptureaudiostatemonitorforcategoryanddeviceid.md)