VB.NET で winusb を使用して USB デバイスに接続する DLL ライブラリを作成しています。
これは DLL であるため、ウィンドウがありません。また、ライブラリのユーザーにもウィンドウがない可能性があります (コマンド ライン アプリなど)。
私が見た例では、デバイスのアタッチとデタッチのすべての使用を検出しますRegisterDeviceNotification。これには、アタッチ/デタッチ メッセージを受信するためのウィンドウ ハンドルが必要です。
これらのメッセージをハンドルを取得するウィンドウなしで関数に直接受け取るにはどうすればよいですか?
私は最近、GUIのないアプリケーションのRegisterDeviceNotificationよりも洗練されているように見えるソリューションを見つけました。
void onEventArrived(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject _o = e.NewEvent["TargetInstance"] as ManagementBaseObject;
if (_o != null)
{
using (ManagementObject mo = new ManagementObject(_o["Dependent"].ToString()))
{
if (mo != null)
{
try
{
if (mo.GetPropertyValue("DeviceID").ToString() != string.Empty)
{
//connected
}
}
catch (ManagementException ex)
{
//disconnected
}
}
}
}
}
を呼び出してこのコードを初期化します
System.Management.WqlEventQuery _q = new WqlEventQuery("__InstanceOperationEvent", "TargetInstance ISA 'Win32_USBControllerDevice' ");
_q.WithinInterval = TimeSpan.FromSeconds(1);
ManagementEventWatcher _w = new ManagementEventWatcher(_q);
_w.EventArrived += new EventArrivedEventHandler(onEventArrived);
_w.Start();
また、System.Managementへの参照を必ず追加してください
これは .NET 用ではありませんが、ウィンドウ コールバックを処理するために必要な構造を作成するプロセスのために C++ でテンプレートを提供し、実際のウィンドウを持たずにカスタム ウィンドウ ハンドルを登録する方法を提供します。
http://msdn.microsoft.com/en-us/library/aa363432%28VS.85%29.aspx
この例では、デバイスの変更通知にウィンドウ ハンドルを使用しており、ウィンドウ メカニズムをサポートする大量のコードが含まれています。Windows サービスとしてインストールされることを意図したアプリケーションには、異なるサポート コードが含まれます。
USB デバイス インターフェイス イベント通知が送信されるたびに、アプリケーションは WM_DEVICECHANGE メッセージを受信します。
システムは、デフォルトのデバイス変更イベントのセットをすべてのアプリケーションとサービスにブロードキャストします。これらのデフォルト イベントを受信するために登録する必要はありません。詳細については、RegisterDeviceNotification の備考セクションを参照してください。
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <strsafe.h> #include <dbt.h> // This GUID is for all USB serial host PnP drivers, but you can replace it // with any valid device class guid. GUID WceusbshGUID = { 0x25dbce51, 0x6c8f, 0x4a72, 0x8a,0x6d,0xb5,0x4c,0x2b,0x4f,0xc8,0x35 }; // For informational messages and window titles PWSTR g_pszAppName; // Forward declarations void OutputMessage(HWND hOutWnd, WPARAM wParam, LPARAM lParam); void ErrorHandler(LPTSTR lpszFunction); // // DoRegisterDeviceInterfaceToHwnd // BOOL DoRegisterDeviceInterfaceToHwnd( IN GUID InterfaceClassGuid, IN HWND hWnd, OUT HDEVNOTIFY *hDeviceNotify ) // Routine Description: // Registers an HWND for notification of changes in the device interfaces // for the specified interface class GUID. // Parameters: // InterfaceClassGuid - The interface class GUID for the device // interfaces. // hWnd - Window handle to receive notifications. // hDeviceNotify - Receives the device notification handle. On failure, // this value is NULL. // Return Value: // If the function succeeds, the return value is TRUE. // If the function fails, the return value is FALSE. // Note: // RegisterDeviceNotification also allows a service handle be used, // so a similar wrapper function to this one supporting that scenario // could be made from this template. { DEV_BROADCAST_DEVICEINTERFACE NotificationFilter; ZeroMemory( &NotificationFilter, sizeof(NotificationFilter) ); NotificationFilter.dbcc_size = sizeof(DEV_BROADCAST_DEVICEINTERFACE); NotificationFilter.dbcc_devicetype = DBT_DEVTYP_DEVICEINTERFACE; NotificationFilter.dbcc_classguid = InterfaceClassGuid; *hDeviceNotify = RegisterDeviceNotification( hWnd, // events recipient &NotificationFilter, // type of device DEVICE_NOTIFY_WINDOW_HANDLE // type of recipient handle ); if ( NULL == *hDeviceNotify ) { ErrorHandler(TEXT("RegisterDeviceNotification")); return FALSE; } return TRUE; } // // MessagePump // void MessagePump( HWND hWnd ) // Routine Description: // Simple main thread message pump. // // Parameters: // hWnd - handle to the window whose messages are being dispatched // Return Value: // None. { MSG msg; int retVal; // Get all messages for any window that belongs to this thread, // without any filtering. Potential optimization could be // obtained via use of filter values if desired. while( (retVal = GetMessage(&msg, NULL, 0, 0)) != 0 ) { if ( retVal == -1 ) { ErrorHandler(TEXT("GetMessage")); break; } else { TranslateMessage(&msg); DispatchMessage(&msg); } } } // // WinProcCallback // INT_PTR WINAPI WinProcCallback( HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam ) // Routine Description: // Simple Windows callback for handling messages. // This is where all the work is done because the example // is using a window to process messages. This logic would be handled // differently if registering a service instead of a window. // Parameters: // hWnd - the window handle being registered for events. // message - the message being interpreted. // wParam and lParam - extended information provided to this // callback by the message sender. // For more information regarding these parameters and return value, // see the documentation for WNDCLASSEX and CreateWindowEx. { LRESULT lRet = 1; static HDEVNOTIFY hDeviceNotify; static HWND hEditWnd; static ULONGLONG msgCount = 0; switch (message) { case WM_CREATE: // // This is the actual registration., In this example, registration // should happen only once, at application startup when the window // is created. // // If you were using a service, you would put this in your main code // path as part of your service initialization. // if ( ! DoRegisterDeviceInterfaceToHwnd( WceusbshGUID, hWnd, &hDeviceNotify) ) { // Terminate on failure. ErrorHandler(TEXT("DoRegisterDeviceInterfaceToHwnd")); ExitProcess(1); } // // Make the child window for output. // hEditWnd = CreateWindow(TEXT("EDIT"),// predefined class NULL, // no window title WS_CHILD | WS_VISIBLE | WS_VSCROLL | ES_LEFT | ES_MULTILINE | ES_AUTOVSCROLL, 0, 0, 0, 0, // set size in WM_SIZE message hWnd, // parent window (HMENU)1, // edit control ID (HINSTANCE) GetWindowLong(hWnd, GWL_HINSTANCE), NULL); // pointer not needed if ( hEditWnd == NULL ) { // Terminate on failure. ErrorHandler(TEXT("CreateWindow: Edit Control")); ExitProcess(1); } // Add text to the window. SendMessage(hEditWnd, WM_SETTEXT, 0, (LPARAM)TEXT("Registered for USB device notification...\n")); break; case WM_SETFOCUS: SetFocus(hEditWnd); break; case WM_SIZE: // Make the edit control the size of the window's client area. MoveWindow(hEditWnd, 0, 0, // starting x- and y-coordinates LOWORD(lParam), // width of client area HIWORD(lParam), // height of client area TRUE); // repaint window break; case WM_DEVICECHANGE: { // // This is the actual message from the interface via Windows messaging. // This code includes some additional decoding for this particular device type // and some common validation checks. // // Note that not all devices utilize these optional parameters in the same // way. Refer to the extended information for your particular device type // specified by your GUID. // PDEV_BROADCAST_DEVICEINTERFACE b = (PDEV_BROADCAST_DEVICEINTERFACE) lParam; TCHAR strBuff[256]; // Output some messages to the window. switch (wParam) { case DBT_DEVICEARRIVAL: msgCount++; StringCchPrintf( strBuff, 256, TEXT("Message %d: DBT_DEVICEARRIVAL\n"), msgCount); break; case DBT_DEVICEREMOVECOMPLETE: msgCount++; StringCchPrintf( strBuff, 256, TEXT("Message %d: DBT_DEVICEREMOVECOMPLETE\n"), msgCount); break; case DBT_DEVNODES_CHANGED: msgCount++; StringCchPrintf( strBuff, 256, TEXT("Message %d: DBT_DEVNODES_CHANGED\n"), msgCount); break; default: msgCount++; StringCchPrintf( strBuff, 256, TEXT("Message %d: WM_DEVICECHANGE message received, value %d unhandled.\n"), msgCount, wParam); break; } OutputMessage(hEditWnd, wParam, (LPARAM)strBuff); } break; case WM_CLOSE: if ( ! UnregisterDeviceNotification(hDeviceNotify) ) { ErrorHandler(TEXT("UnregisterDeviceNotification")); } DestroyWindow(hWnd); break; case WM_DESTROY: PostQuitMessage(0); break; default: // Send all other messages on to the default windows handler. lRet = DefWindowProc(hWnd, message, wParam, lParam); break; } return lRet; } #define WND_CLASS_NAME TEXT("SampleAppWindowClass") // // InitWindowClass // BOOL InitWindowClass() // Routine Description: // Simple wrapper to initialize and register a window class. // Parameters: // None // Return Value: // TRUE on success, FALSE on failure. // Note: // wndClass.lpfnWndProc and wndClass.lpszClassName are the // important unique values used with CreateWindowEx and the // Windows message pump. { WNDCLASSEX wndClass; wndClass.cbSize = sizeof(WNDCLASSEX); wndClass.style = CS_OWNDC | CS_HREDRAW | CS_VREDRAW; wndClass.hInstance = reinterpret_cast<HINSTANCE>(GetModuleHandle(0)); wndClass.lpfnWndProc = reinterpret_cast<WNDPROC>(WinProcCallback); wndClass.cbClsExtra = 0; wndClass.cbWndExtra = 0; wndClass.hIcon = LoadIcon(0,IDI_APPLICATION); wndClass.hbrBackground = CreateSolidBrush(RGB(192,192,192)); wndClass.hCursor = LoadCursor(0, IDC_ARROW); wndClass.lpszClassName = WND_CLASS_NAME; wndClass.lpszMenuName = NULL; wndClass.hIconSm = wndClass.hIcon; if ( ! RegisterClassEx(&wndClass) ) { ErrorHandler(TEXT("RegisterClassEx")); return FALSE; } return TRUE; } // // main // int __stdcall _tWinMain( HINSTANCE hInstanceExe, HINSTANCE, // should not reference this parameter PTSTR lpstrCmdLine, int nCmdShow ) { // // To enable a console project to compile this code, set // Project->Properties->Linker->System->Subsystem: Windows. // int nArgC = 0; PWSTR* ppArgV = CommandLineToArgvW(lpstrCmdLine, &nArgC); g_pszAppName = ppArgV[0]; if ( ! InitWindowClass() ) { // InitWindowClass displays any errors return -1; } // Main app window HWND hWnd = CreateWindowEx( WS_EX_CLIENTEDGE | WS_EX_APPWINDOW, WND_CLASS_NAME, g_pszAppName, WS_OVERLAPPEDWINDOW, // style CW_USEDEFAULT, 0, 640, 480, NULL, NULL, hInstanceExe, NULL); if ( hWnd == NULL ) { ErrorHandler(TEXT("CreateWindowEx: main appwindow hWnd")); return -1; } // Actually draw the window. ShowWindow(hWnd, SW_SHOWNORMAL); UpdateWindow(hWnd); // The message pump loops until the window is destroyed. MessagePump(hWnd); return 1; } // // OutputMessage // void OutputMessage( HWND hOutWnd, WPARAM wParam, LPARAM lParam ) // Routine Description: // Support routine. // Send text to the output window, scrolling if necessary. // Parameters: // hOutWnd - Handle to the output window. // wParam - Standard windows message code, not used. // lParam - String message to send to the window. // Return Value: // None // Note: // This routine assumes the output window is an edit control // with vertical scrolling enabled. // This routine has no error checking. { LRESULT lResult; LONG bufferLen; LONG numLines; LONG firstVis; // Make writable and turn off redraw. lResult = SendMessage(hOutWnd, EM_SETREADONLY, FALSE, 0L); lResult = SendMessage(hOutWnd, WM_SETREDRAW, FALSE, 0L); // Obtain current text length in the window. bufferLen = SendMessage (hOutWnd, WM_GETTEXTLENGTH, 0, 0L); numLines = SendMessage (hOutWnd, EM_GETLINECOUNT, 0, 0L); firstVis = SendMessage (hOutWnd, EM_GETFIRSTVISIBLELINE, 0, 0L); lResult = SendMessage (hOutWnd, EM_SETSEL, bufferLen, bufferLen); // Write the new text. lResult = SendMessage (hOutWnd, EM_REPLACESEL, 0, lParam); // See whether scrolling is necessary. if (numLines > (firstVis + 1)) { int lineLen = 0; int lineCount = 0; int charPos; // Find the last nonblank line. numLines--; while(!lineLen) { charPos = SendMessage( hOutWnd, EM_LINEINDEX, (WPARAM)numLines, 0L); lineLen = SendMessage( hOutWnd, EM_LINELENGTH, charPos, 0L); if(!lineLen) numLines--; } // Prevent negative value finding min. lineCount = numLines - firstVis; lineCount = (lineCount >= 0) ? lineCount : 0; // Scroll the window. lResult = SendMessage( hOutWnd, EM_LINESCROLL, 0, (LPARAM)lineCount); } // Done, make read-only and allow redraw. lResult = SendMessage(hOutWnd, WM_SETREDRAW, TRUE, 0L); lResult = SendMessage(hOutWnd, EM_SETREADONLY, TRUE, 0L); } // // ErrorHandler // void ErrorHandler( LPTSTR lpszFunction ) // Routine Description: // Support routine. // Retrieve the system error message for the last-error code // and pop a modal alert box with usable info. // Parameters: // lpszFunction - String containing the function name where // the error occurred plus any other relevant data you'd // like to appear in the output. // Return Value: // None // Note: // This routine is independent of the other windowing routines // in this application and can be used in a regular console // application without modification. { LPVOID lpMsgBuf; LPVOID lpDisplayBuf; DWORD dw = GetLastError(); FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, dw, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR) &lpMsgBuf, 0, NULL ); // Display the error message and exit the process. lpDisplayBuf = (LPVOID)LocalAlloc(LMEM_ZEROINIT, (lstrlen((LPCTSTR)lpMsgBuf) + lstrlen((LPCTSTR)lpszFunction)+40) * sizeof(TCHAR)); StringCchPrintf((LPTSTR)lpDisplayBuf, LocalSize(lpDisplayBuf) / sizeof(TCHAR), TEXT("%s failed with error %d: %s"), lpszFunction, dw, lpMsgBuf); MessageBox(NULL, (LPCTSTR)lpDisplayBuf, g_pszAppName, MB_OK); LocalFree(lpMsgBuf); LocalFree(lpDisplayBuf); }SDK または Visual Studio コマンド プロンプトから nmake.exe を使用して前のサンプル コードをビルドするための makefile の例を次に示します。
proj = main all: $(proj).exe # Update the object file if necessary $(proj).obj: $(proj).cpp cl -c /D_UNICODE /DUNICODE -DWIN32 -D_WIN32 -DNDEBUG -GS -D_X86_=1 -D_WIN32_WINNT=0x0501 -DCRTAPI1=_cdecl -DCRTAPI2=_cdecl -D_MT -D_DLL -MD $*.cpp # Update the executable file if necessary $(proj).exe: $(proj).obj link -release -incremental:no -nologo -subsystem:windows,5.01 $(proj).obj kernel32.lib user32.lib advapi32.lib gdi32.lib shell32.lib -out:$(proj).exe