WinBioEnrollCaptureWithCallback 函数 (winbio.h)
异步捕获生物识别示例并将其添加到模板。 函数立即返回调用方,在单独的线程上执行注册,并调用应用程序定义的回调函数以更新操作状态。
建议从 Windows 8 开始,不再使用此函数来启动异步操作。 请改为执行以下操作:
- 实现 PWINBIO_ASYNC_COMPLETION_CALLBACK 函数,以在操作完成时接收通知。
- 调用 WinBioAsyncOpenSession 函数。 在 CallbackRoutine 参数中传递回调的地址。 在 NotificationMethod 参数中传递WINBIO_ASYNC_NOTIFY_CALLBACK。 检索异步会话句柄。
- 使用异步会话句柄调用 WinBioEnrollCapture。 操作完成后,Windows 生物识别框架将使用结果分配和初始化 WINBIO_ASYNC_RESULT 结构,并使用指向结果结构的指针调用回调。
- 从回调实现调用 WinBioFree ,以在使用完 WINBIO_ASYNC_RESULT 结构后释放它。
语法
HRESULT WinBioEnrollCaptureWithCallback(
[in] WINBIO_SESSION_HANDLE SessionHandle,
[in] PWINBIO_ENROLL_CAPTURE_CALLBACK EnrollCallback,
[in, optional] PVOID EnrollCallbackContext
);
参数
[in] SessionHandle
标识打开的生物识别会话 的WINBIO_SESSION_HANDLE 值。
[in] EnrollCallback
捕获操作成功或失败时由 WinBioEnrollCaptureWithCallback 函数调用的回调函数的地址。 必须创建回调。
[in, optional] EnrollCallbackContext
指向传递给回调函数的 EnrollCallbackContext 参数的可选应用程序定义结构的指针。 此结构可以包含自定义回调函数旨在处理的任何数据。
返回值
如果函数成功,则返回 S_OK。 如果函数失败,它将返回一个 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 通用 HRESULT 值。
返回代码 | 说明 |
---|---|
|
不允许调用帐户执行注册。 |
|
会话句柄无效。 |
|
由 EnrollCallback 参数指定的指针不能为 NULL。 |
注解
如果 SessionHandle 参数引用系统传感器池,则在应用程序获取窗口焦点并且用户提供生物识别示例之前,不会调用回调函数。 获取焦点的方式取决于正在编写的应用程序类型。 例如,如果要创建 GUI 应用程序,则可以实现捕获 WM_ACTIVATE、 WM_SETFOCUS或其他相应消息的消息处理程序。 如果要编写 CUI 应用程序,请调用 GetConsoleWindow 以检索控制台窗口的句柄,并将该句柄传递给 SetForegroundWindow 函数,以强制控制台窗口进入前台并为其分配焦点。 如果应用程序在分离进程中运行,并且没有窗口或是 Windows 服务,请使用 WinBioAcquireFocus 和 WinBioReleaseFocus 手动控制焦点。
示例
下面的代码示例通过调用 WinBioEnrollCaptureWithCallback 并将指针传递到自定义回调函数来异步注册指纹。 还显示了回调函数 EnrollCaptureCallback。 链接到 Winbio.lib 静态库。
//------------------------------------------------------------------------
// 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;
}
要求
要求 | 值 |
---|---|
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 |