PWINBIO_ENROLL_CAPTURE_CALLBACK fungsi panggilan balik (winbio.h)

Fungsi PWINBIO_ENROLL_CAPTURE_CALLBACK dipanggil oleh Windows Biometric Framework untuk mengembalikan hasil dari fungsi WinBioEnrollCaptureWithCallback asinkron. Aplikasi klien harus menerapkan fungsi ini.

Penting Kami menyarankan agar, dimulai dengan Windows 8, Anda tidak lagi menggunakan kombinasiWinBioEnrollCaptureWithCallbackPWINBIO_ENROLL_CAPTURE_CALLBACK/. Sebagai gantinya, lakukan hal berikut:

• Terapkan fungsi PWINBIO_ASYNC_COMPLETION_CALLBACK untuk menerima pemberitahuan ketika operasi selesai.
• Panggil fungsi WinBioAsyncOpenSession . Berikan alamat panggilan balik Anda di parameter CallbackRoutine . Teruskan WINBIO_ASYNC_NOTIFY_CALLBACK di parameter NotificationMethod . Ambil handel sesi asinkron.
• Gunakan handel sesi asinkron untuk memanggil WinBioEnrollCapture. Ketika operasi selesai, Windows Biometric Framework akan mengalokasikan dan menginisialisasi struktur WINBIO_ASYNC_RESULT dengan hasil dan memanggil panggilan balik Anda dengan penunjuk ke struktur hasil.
• Panggil WinBioFree dari implementasi panggilan balik Anda untuk merilis struktur WINBIO_ASYNC_RESULT setelah Anda selesai menggunakannya.

 

Sintaks

PWINBIO_ENROLL_CAPTURE_CALLBACK PwinbioEnrollCaptureCallback;

void PwinbioEnrollCaptureCallback(
  [in, optional] PVOID EnrollCallbackContext,
  [in]           HRESULT OperationStatus,
  [in]           WINBIO_REJECT_DETAIL RejectDetail
)
{...}

Parameter

[in, optional] EnrollCallbackContext

Pointer ke buffer yang ditentukan oleh aplikasi dan diteruskan ke parameter EnrollCallback dari fungsi WinBioEnrollCaptureWithCallback . Buffer tidak dimodifikasi oleh kerangka kerja atau unit biometrik. Aplikasi Anda dapat menggunakan data untuk membantu menentukan tindakan apa yang harus dilakukan atau mempertahankan informasi tambahan tentang pengambilan biometrik.

[in] OperationStatus

Kode kesalahan yang dikembalikan oleh operasi penangkapan.

[in] RejectDetail

Informasi tambahan tentang kegagalan, jika ada, untuk melakukan operasi. Untuk informasi selengkapnya, lihat Keterangan.

Mengembalikan nilai

Tidak ada

Keterangan

Saat ini, Windows Biometric Framework hanya mendukung pembaca sidik jari. Oleh karena itu, jika operasi gagal dan mengembalikan informasi tambahan dalam konstanta WINBIO_REJECT_DETAIL , itu akan menjadi salah satu nilai berikut:

• WINBIO_FP_TOO_HIGH
• WINBIO_FP_TOO_LOW
• WINBIO_FP_TOO_LEFT
• WINBIO_FP_TOO_RIGHT
• WINBIO_FP_TOO_FAST
• WINBIO_FP_TOO_SLOW
• WINBIO_FP_POOR_QUALITY
• WINBIO_FP_TOO_SKEWED
• WINBIO_FP_TOO_SHORT
• WINBIO_FP_MERGE_FAILURE

Contoh

Contoh kode berikut mendaftarkan sidik jari secara asinkron dengan memanggil WinBioEnrollCaptureWithCallback dan meneruskan pointer ke fungsi panggilan balik kustom, EnrollCaptureCallback. Tautan ke pustaka statis Winbio.lib.

//------------------------------------------------------------------------
// EnrollSystemPoolWithCallback.cpp : console application entry point.
//

#include <windows.h>
#include <stdio.h>
#include <conio.h>
#include <winbio.h>


//------------------------------------------------------------------------
// Forward declarations.
//
HRESULT EnrollSysPoolWithCallback(
                      BOOL bCancel,
                      BOOL bDiscard,
                      WINBIO_BIOMETRIC_SUBTYPE subFactor);

VOID CALLBACK EnrollCaptureCallback(
                      __in_opt PVOID EnrollCallbackContext,
                      __in HRESULT OperationStatus,
                      __in WINBIO_REJECT_DETAIL RejectDetail);

typedef struct _ENROLL_CALLBACK_CONTEXT {
    WINBIO_SESSION_HANDLE SessionHandle;
    WINBIO_UNIT_ID UnitId;
    WINBIO_BIOMETRIC_SUBTYPE SubFactor;
} ENROLL_CALLBACK_CONTEXT, *PENROLL_CALLBACK_CONTEXT;

//------------------------------------------------------------------------
int wmain()
{
    HRESULT hr = S_OK;

    hr = EnrollSysPoolWithCallback(
                      FALSE, 
                      FALSE, 
                      WINBIO_ANSI_381_POS_RH_INDEX_FINGER);

    return 0;
}

//------------------------------------------------------------------------
// The following function enrolls a user's fingerprint in the system pool.
// The function calls WinBioEnrollCaptureWithCallback and waits for the
// asynchronous enrollment process to be completed or canceled.
//
HRESULT EnrollSysPoolWithCallback(
                      BOOL bCancel,
                      BOOL bDiscard,
                      WINBIO_BIOMETRIC_SUBTYPE subFactor)
{
    // Declare variables
    HRESULT hr = S_OK;
    WINBIO_IDENTITY identity = {0};
    WINBIO_SESSION_HANDLE sessionHandle = NULL;
    WINBIO_UNIT_ID unitId = 0;
    BOOLEAN isNewTemplate = TRUE;
    ENROLL_CALLBACK_CONTEXT callbackContext = {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 WinBioEnumBiometricUnits failed. ");
        wprintf_s(L"hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Locate the sensor.
    wprintf_s(L"\n Swipe your finger to locate the sensor...\n");
    hr = WinBioLocateSensor( sessionHandle, &unitId);
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioLocateSensor failed. hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Begin the enrollment sequence. 
    hr = WinBioEnrollBegin(
            sessionHandle,      // Handle to open biometric session
            subFactor,          // Finger to create template for
            unitId              // Biometric unit ID
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioEnrollBegin failed. hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Set up the custom callback context structure.
    callbackContext.SessionHandle = sessionHandle;
    callbackContext.UnitId = unitId;
    callbackContext.SubFactor = subFactor;

    // Call WinBioEnrollCaptureWithCallback. This is an asynchronous
    // method that returns immediately.
    hr = WinBioEnrollCaptureWithCallback(
            sessionHandle,          // Handle to open biometric session
            EnrollCaptureCallback,  // Callback function
            &callbackContext        // Pointer to the custom context
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioEnrollCaptureWithCallback failed. ");
        wprintf_s(L"hr = 0x%x\n", hr);
        goto e_Exit;
    }
    wprintf_s(L"\n Swipe the sensor with the appropriate finger...\n");

    // Cancel the enrollment 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 the asynchronous enrollment process to complete
    // or be canceled.
    hr = WinBioWait( sessionHandle );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioWait failed. hr = 0x%x\n", hr);
    }

    // Discard the enrollment if the bDiscard flag is set.
    // Commit the enrollment if the flag is not set.
    if (bDiscard)
    {
        wprintf_s(L"\n Discarding enrollment...\n");
        hr = WinBioEnrollDiscard( sessionHandle );
        if (FAILED(hr))
        {
            wprintf_s(L"\n WinBioLocateSensor failed. ");
            wprintf_s(L"hr = 0x%x\n", hr);
        }
        goto e_Exit;    
    }
    else
    {
        wprintf_s(L"\n Committing enrollment...\n");
        hr = WinBioEnrollCommit( 
                sessionHandle,      // Handle to open biometric session
                &identity,          // WINBIO_IDENTITY object for the user
                &isNewTemplate);    // Is this a new template

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

e_Exit:
    if (sessionHandle != NULL)
    {
        WinBioCloseSession(sessionHandle);
        sessionHandle = NULL;
    }

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

    return hr;
}

//------------------------------------------------------------------------
// The following function is the callback for the Windows Biometric
// Framework WinBioEnrollCaptureWithCallback() function. 
//
VOID CALLBACK EnrollCaptureCallback(
    __in_opt PVOID EnrollCallbackContext,
    __in HRESULT OperationStatus,
    __in WINBIO_REJECT_DETAIL RejectDetail
    )
{
    // Declare variables.
    HRESULT hr = S_OK; 
    static SIZE_T swipeCount = 1;

    PENROLL_CALLBACK_CONTEXT callbackContext = 
        (PENROLL_CALLBACK_CONTEXT)EnrollCallbackContext;

    wprintf_s(L"\n EnrollCaptureCallback executing\n");
    wprintf_s(L"\n Sample %d captured", swipeCount++);

    // The capture was not acceptable or the enrollment operation
    // failed.
    if (FAILED(OperationStatus))
    {
        if (OperationStatus == WINBIO_E_BAD_CAPTURE)
        {
            wprintf_s(L"\n Bad capture; reason: %d\n", RejectDetail);
            wprintf_s(L"\n Swipe your finger to capture another sample.\n");

            // Try again.
            hr = WinBioEnrollCaptureWithCallback(
                    callbackContext->SessionHandle, // Open session handle
                    EnrollCaptureCallback,          // Callback function
                    EnrollCallbackContext           // Callback context
                    );
            if (FAILED(hr))
            {
                wprintf_s(L"WinBioEnrollCaptureWithCallback failed.");
                wprintf_s(L"hr = 0x%x\n", hr);
            }
        }
        else
        {
            wprintf_s(L"EnrollCaptureCallback failed.");
            wprintf_s(L"OperationStatus = 0x%x\n", OperationStatus);
        }
        goto e_Exit;
    }

    // The enrollment operation requires more fingerprint swipes.
    // This is normal and depends on your hardware. Typically, at least
    // three swipes are required.
    if (OperationStatus == WINBIO_I_MORE_DATA)
    {
        wprintf_s(L"\n More data required.");
        wprintf_s(L"\n Swipe your finger on the sensor again.");

        hr = WinBioEnrollCaptureWithCallback(
                callbackContext->SessionHandle,
                EnrollCaptureCallback,
                EnrollCallbackContext
                );
        if (FAILED(hr))
        {
            wprintf_s(L"WinBioEnrollCaptureWithCallback failed. ");
            wprintf_s(L"hr = 0x%x\n", hr);
        }
        goto e_Exit;
    }

    wprintf_s(L"\n Template completed\n");

e_Exit:

    return;
}

Persyaratan

Persyaratan	Nilai
Klien minimum yang didukung	Windows 7 [hanya aplikasi desktop]
Server minimum yang didukung	Windows Server 2008 R2 [hanya aplikasi desktop]
Target Platform	Windows
Header	winbio.h