WinBioUnregisterEventMonitor 函数 (winbio.h)

WinBioUnregisterEventMonitor 函数取消来自与打开的生物识别会话关联的服务提供商的事件通知。

语法

HRESULT WinBioUnregisterEventMonitor(
  [in] WINBIO_SESSION_HANDLE SessionHandle
);

参数

[in] SessionHandle

标识打开的生物识别会话 的WINBIO_SESSION_HANDLE 值。 通过调用 WinBioOpenSession 打开会话句柄。

返回值

如果函数成功,则返回S_OK。 如果函数失败,它将返回指示错误的 HRESULT 值。 可能的值包括(但并不限于)下表中的项。 有关常见错误代码的列表,请参阅 常见 HRESULT 值

返回代码 说明
E_HANDLE
会话句柄无效。

注解

调用 WinBioRegisterEventMonitor 函数以开始接收事件通知。

如果应用程序注册 WinBio 事件监视器并在睡眠/唤醒周期期间使该监视器保持活动状态,则实施生物识别预启动身份验证 (PBA) /单一登录功能的系统可能无法始终正常工作。 问题是,在系统的生物识别凭据提供程序有机会执行其第一个 WinBioIdentify 操作之前,事件监视器截获了 PBA 生物识别调用。 使用 WinBio 事件监视功能的应用应在系统睡眠前注销其监视器,并在系统唤醒后重新注册它们。 有关在电源状态更改期间处理事件的详细信息,请参阅 关于电源管理

示例

以下函数通过调用 WinBioRegisterEventMonitor 函数并传递回调例程的地址来注册事件监视器。 回调(还包括)接收来自 Windows 生物识别框架的事件通知。 该函数还会在关闭生物识别会话之前调用 WinBioUnregisterEventMonitor 。 链接到 Winbio.lib 静态库并包含以下头文件:

  • Windows.h
  • Stdio.h
  • Conio.h
  • Winbio.h
HRESULT RegisterSystemEventMonitor(BOOL bCancel)
{
    HRESULT hr = S_OK;
    WINBIO_SESSION_HANDLE sessionHandle = NULL;
    WINBIO_UNIT_ID unitId = 0;

    // Connect to the system pool. 
    hr = WinBioOpenSession( 
            WINBIO_TYPE_FINGERPRINT,    // Service provider
            WINBIO_POOL_SYSTEM,         // Pool type
            WINBIO_FLAG_DEFAULT,        // Configuration and access
            NULL,                       // Array of biometric unit IDs
            0,                          // Count of biometric unit IDs
            NULL,                       // Database ID
            &sessionHandle              // [out] Session handle
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioOpenSession failed. hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Call the WinBioRegisterEventMonitor function.
    wprintf_s(L"\n Calling WinBioRegisterEventMonitor.\n");
    hr = WinBioRegisterEventMonitor(
            sessionHandle,              // Open session handle
            WINBIO_EVENT_FP_UNCLAIMED,  // Events to monitor
            EventMonitorCallback,       // Callback function
            NULL                        // Optional context.
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioRegisterEventMonitor failed.");
        wprintf_s(L"hr = 0x%x\n", hr);
        goto e_Exit;
    }
    wprintf_s(L"\n Waiting for an event.\n");


    // Cancel the identification if the bCancel flag is set.
    if (bCancel)
    {
        wprintf_s(L"\n Starting CANCEL timer...\n");
        Sleep( 7000 );

        wprintf_s(L"\n Calling WinBioCancel\n");
        hr = WinBioCancel( sessionHandle );
        if (FAILED(hr))
        {
            wprintf_s(L"\n WinBioCancel failed. hr = 0x%x\n", hr);
            goto e_Exit;
        }
    }

    // Wait for an event to happen.
    //wprintf_s(L"\n Swipe the sensor to receive an event notice ");
    //wprintf_s(L"\n or press any key to stop waiting...\n");
    wprintf_s(L"\n Swipe the sensor one or more times ");
    wprintf_s(L"to generate events.");
    wprintf_s(L"\n When done, press a key to exit...\n");
    _getch();

    // Unregister the event monitor.
    wprintf_s(L"\n Calling WinBioUnregisterEventMonitor\n");
    hr = WinBioUnregisterEventMonitor( sessionHandle);
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioUnregisterEventMonitor failed.");
        wprintf_s(L"hr = 0x%x\n", hr);
    }

e_Exit:

    if (sessionHandle != NULL)
    {
       wprintf_s(L"\n Closing the session.\n");

        hr = WinBioCloseSession(sessionHandle);
        if (FAILED(hr))
        {
            wprintf_s(L"\n WinBioCloseSession failed. hr = 0x%x\n", hr);
        }
        sessionHandle = NULL;
    }

    wprintf_s(L"\n Press any key to exit...");
    _getch();

    return hr;
}

//------------------------------------------------------------------------
// The following function is the callback for WinBioRegisterEventMonitor.
// The function filters any event notice from the biometric subsystem and 
// writes a result to the console window.
// 
VOID CALLBACK EventMonitorCallback(
    __in_opt PVOID EventCallbackContext,
    __in HRESULT OperationStatus,
    __in PWINBIO_EVENT Event
    )
{
    UNREFERENCED_PARAMETER(EventCallbackContext);

    wprintf_s(L"\n EventMonitorCallback executing.");

    // Failure.
    if (FAILED(OperationStatus))
    {
        wprintf_s(L"\n EventMonitorCallback failed. ");
        wprintf_s(L" OperationStatus = 0x%x\n", OperationStatus);
        goto e_Exit;
    }

    // An event notice was received.
    if (Event != NULL)
    {
        wprintf_s(L"\n MonitorEvent: ");
        switch (Event->Type)
        {
            case WINBIO_EVENT_FP_UNCLAIMED:
                wprintf_s(L"WINBIO_EVENT_FP_UNCLAIMED");
                wprintf_s(L"\n Unit ID: %d", 
                          Event->Parameters.Unclaimed.UnitId);
                wprintf_s(L"\n Reject detail: %d\n", 
                          Event->Parameters.Unclaimed.RejectDetail);
                break;

            case WINBIO_EVENT_FP_UNCLAIMED_IDENTIFY:
                wprintf_s(L"WINBIO_EVENT_FP_UNCLAIMED_IDENTIFY");
                wprintf_s(L"\n Unit ID: %d", 
                          Event->Parameters.UnclaimedIdentify.UnitId);
                wprintf_s(L"\n Reject detail: %d\n", 
                          Event->Parameters.UnclaimedIdentify.RejectDetail);
                break;

            case WINBIO_EVENT_ERROR:
                wprintf_s(L"WINBIO_EVENT_ERROR\n");
                break;

            default:
                wprintf_s(L"(0x%08x - Invalid type)\n", Event->Type);
                break;
        }
    }

e_Exit:

    if (Event != NULL)
    {
        //wprintf_s(L"\n Press any key to continue...\n");
        WinBioFree(Event);
        Event = NULL;
    }
}


要求

要求
最低受支持的客户端 Windows 7 [仅限桌面应用]
最低受支持的服务器 Windows Server 2008 R2 [仅限桌面应用]
目标平台 Windows
标头 winbio.h (包括 Winbio.h)
Library Winbio.lib
DLL Winbio.dll

另请参阅

WinBioRegisterEventMonitor