> ## 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.

# XUserRegisterForChangeEvent

> XUserRegisterForChangeEvent

# XUserRegisterForChangeEvent

為使用者變更事件註冊回呼。

## 語法

```cpp theme={null}
HRESULT XUserRegisterForChangeEvent(  
         XTaskQueueHandle queue,  
         void* context,  
         XUserChangeEventCallback* callback,  
         XTaskQueueRegistrationToken* token  
)  
```

### 參數

*queue*   \_In\_opt\_\
類型：XTaskQueueHandle

要在其上執行作業之非同步佇列的控制代碼。

*context*   \_In\_opt\_\
類型：void\*

要傳遞給回呼的使用者定義內容。

*callback*   \_In\_\
類型：[XUserChangeEventCallback\*](/zh-TW/reference/system/xuser/functions/xuserchangeeventcallback)

要註冊的使用者定義回呼。

*token*   \_Out\_\
類型：[XTaskQueueRegistrationToken\*](/zh-TW/reference/system/xtaskqueue/structs/xtaskqueueregistrationtoken)

包含識別已註冊回呼的權杖。請使用此權杖取消註冊回呼。

### 傳回值

類型：HRESULT

HRESULT 成功或錯誤碼。\
如需錯誤碼清單，請參閱[錯誤碼](/zh-TW/reference/errorcodes)。

## 備註

<Note>在時間敏感執行緒上呼叫此函式並不安全。如需詳細資訊，請參閱[時間敏感執行緒](https://learn.microsoft.com/gaming/gdk/docs/gdk-dev/console-dev/overviews/threads/time-sensitive-threads)。</Note>

[XUserChangeEvent](/zh-TW/reference/system/xuser/enums/xuserchangeevent) 列舉會指定變更事件類型。
[XUserChangeEventCallback](/zh-TW/reference/system/xuser/functions/xuserchangeeventcallback) 是使用者變更事件的回呼。

若要取消註冊先前註冊的使用者變更回呼，請呼叫 [XUserUnregisterForChangeEvent](/zh-TW/reference/system/xuser/functions/xuserunregisterforchangeevent)。

下列範例示範如何處理使用者變更事件。

```cpp theme={null}
HRESULT RegisterForChanges()
{
    RETURN_HR_IF(E_UNEXPECTED, _token.token != 0);
    RETURN_IF_FAILED(XUserRegisterForChangeEvent(
        _queue,
        this,
        UserChangeEventHandler,
        &_token));
    return S_OK;
}

void UnregisterForChanges()
{
    XUserUnregisterForChangeEvent(_token, false);
    _token.token = 0;
}

void UserChangeEventHandler(
    XUserLocalId userLocalId,
    XUserChangeEvent event)
{
    auto iter = std::find_if(
        _users.begin(),
        _users.end(),
        [&userLocalId](const User& candidate)
    {
        XUserLocalId candidateUserLocalId;
        XUserGetLocalId(candidate.Handle(), &candidateUserLocalId);
        return candidateUserLocalId == userLocalId;
    });

    // User not known
    if (iter == _users.end())
    {
        return;
    }

    auto handle = iter->Handle();

    // If a guest gets signed out, immediately close the handle
    bool isGuest;
    if (SUCCEEDED_LOG(XUserGetIsGuest(handle, &isGuest)) &&
        isGuest &&
        event == XUserChangeEvent::SignedOut)
    {
        _users.erase(iter);
    }

    if (event == XUserChangeEvent::SigningOut)
    {
        // Delay the user signing out just for fun
        XUserSignOutDeferralHandle deferral;
        if (SUCCEEDED_LOG(XUserGetSignOutDeferral(&deferral)))
        {
            // Hold the deferral for 5 seconds then close it
            std::thread completeDeferralThread(
                [deferral]()
            {
                std::this_thread::sleep_for(std::chrono::milliseconds(5000));
                XUserCloseSignOutDeferralHandle(deferral);
            });

            completeDeferralThread.detach();
        }
    }

    if (event == XUserChangeEvent::GamerPicture)
    {
        iter->LoadGamerPicAsync(_queue);
    }
}
```

## 需求

**標頭：** XUser.h

**程式庫：** xgameruntime.lib

**支援的平台：** Windows、Steam Deck、XBOX One 系列主機和 XBOX Series 主機

## 概念文件

* [時間敏感執行緒](https://learn.microsoft.com/gaming/gdk/docs/gdk-dev/console-dev/overviews/threads/time-sensitive-threads)
* [在遊戲中實作玩家登入](https://learn.microsoft.com/gaming/gdk/docs/gdk-dev/pc-dev/tutorials/pc-e2e-guide/e2e-services/e2e-user-sign-in)

## 另請參閱

[XUser](/zh-TW/reference/system/xuser/xuser_members)

[XUserChangeEvent](/zh-TW/reference/system/xuser/enums/xuserchangeevent)

[XUserChangeEventCallback](/zh-TW/reference/system/xuser/functions/xuserchangeeventcallback)

[XUserUnregisterForChangeEvent](/zh-TW/reference/system/xuser/functions/xuserunregisterforchangeevent)


## Related topics

- [XUserRegisterForChangeEvent](/reference/system/xuser/functions/xuserregisterforchangeevent.md)
- [XUserChangeEvent](/reference/system/xuser/enums/xuserchangeevent.md)
- [XUserUnregisterForChangeEvent](/reference/system/xuser/functions/xuserunregisterforchangeevent.md)
- [XUserChangeEventCallback](/reference/system/xuser/functions/xuserchangeeventcallback.md)
- [XUserGetIsGuest](/reference/system/xuser/functions/xusergetisguest.md)