delphiを使用してプログラムでUSBフラッシュディスクを検出して削除するにはどうすればよいですか？
私はこのウェブサイトでいくつかの例を見ましたが、それらはそれについてどうやって行くかについての明確な説明を欠いています！
例が本当に役立ちます！
12115 次
3 に答える
4
USB ドライブを取り外すための鍵は、CM_Request_Device_Eject関数を使用することです。
この記事に基づいてHow to Prepare a USB Drive for Safe Removalおり、JEDI API Library & Security Code Library
{$APPTYPE CONSOLE}
{$R *.res}
uses
JwaWinIoctl,
Cfg,
CfgMgr32,
SetupApi,
Windows,
SysUtils;
function GetDrivesDevInstByDeviceNumber(DeviceNumber : LONG; DriveType : UINT; szDosDeviceName: PChar) : DEVINST;
var
StorageGUID : TGUID;
IsFloppy : Boolean;
hDevInfo : SetupApi.HDEVINFO;
dwIndex : DWORD;
res : BOOL;
pspdidd : PSPDeviceInterfaceDetailData;
spdid : SP_DEVICE_INTERFACE_DATA;
spdd : SP_DEVINFO_DATA;
dwSize : DWORD;
hDrive : THandle;
sdn : STORAGE_DEVICE_NUMBER;
dwBytesReturned : DWORD;
begin
Result:=0;
IsFloppy := pos('\\Floppy', szDosDeviceName)>0; // who knows a better way?
case DriveType of
DRIVE_REMOVABLE:
if ( IsFloppy ) then
StorageGUID := GUID_DEVINTERFACE_FLOPPY
else
StorageGUID := GUID_DEVINTERFACE_DISK;
DRIVE_FIXED: StorageGUID := GUID_DEVINTERFACE_DISK;
DRIVE_CDROM: StorageGUID := GUID_DEVINTERFACE_CDROM;
else
exit
end;
// Get device interface info set handle for all devices attached to system
hDevInfo := SetupDiGetClassDevs(@StorageGUID, nil, 0, DIGCF_PRESENT OR DIGCF_DEVICEINTERFACE);
if (NativeUInt(hDevInfo) <> INVALID_HANDLE_VALUE) then
try
// Retrieve a context structure for a device interface of a device information set
dwIndex := 0;
//PSP_DEVICE_INTERFACE_DETAIL_DATA pspdidd = (PSP_DEVICE_INTERFACE_DETAIL_DATA)Buf;
spdid.cbSize := SizeOf(spdid);
while true do
begin
res := SetupDiEnumDeviceInterfaces(hDevInfo, nil, StorageGUID, dwIndex, spdid);
if not res then
break;
dwSize := 0;
SetupDiGetDeviceInterfaceDetail(hDevInfo, @spdid, nil, 0, dwSize, nil); // check the buffer size
if ( dwSize<>0) then
begin
pspdidd := AllocMem(dwSize);
try
pspdidd.cbSize := SizeOf(TSPDeviceInterfaceDetailData);
ZeroMemory(@spdd, sizeof(spdd));
spdd.cbSize := SizeOf(spdd);
res := SetupDiGetDeviceInterfaceDetail(hDevInfo, @spdid, pspdidd, dwSize, dwSize, @spdd);
if res then
begin
// open the disk or cdrom or floppy
hDrive := CreateFile(pspdidd.DevicePath, 0, FILE_SHARE_READ OR FILE_SHARE_WRITE, nil, OPEN_EXISTING, 0, 0);
if ( hDrive <> INVALID_HANDLE_VALUE ) then
try
// get its device number
dwBytesReturned := 0;
res := DeviceIoControl(hDrive, IOCTL_STORAGE_GET_DEVICE_NUMBER, nil, 0, @sdn, sizeof(sdn), dwBytesReturned, nil);
if res then
begin
if ( DeviceNumber = sdn.DeviceNumber) then
begin // match the given device number with the one of the current device
Result:= spdd.DevInst;
exit;
end;
end;
finally
CloseHandle(hDrive);
end;
end;
finally
FreeMem(pspdidd);
end;
end;
Inc(dwIndex);
end;
finally
SetupDiDestroyDeviceInfoList(hDevInfo);
end;
end;
procedure EjectUSB(const DriveLetter:char);
var
szRootPath, szDevicePath : PChar;
szVolumeAccessPath : PChar;
hVolume : THandle;
DeviceNumber : LONG;
sdn : STORAGE_DEVICE_NUMBER;
dwBytesReturned : DWORD;
res : BOOL;
resCM : Cardinal;
DriveType : UINT;
szDosDeviceName : array [0..MAX_PATH-1] of Char;
DevInst : CfgMgr32.DEVINST;
VetoType : PNP_VETO_TYPE;
VetoName : array [0..MAX_PATH-1] of WCHAR;
bSuccess : Boolean;
DevInstParent : CfgMgr32.DEVINST;
tries : Integer;
begin
szRootPath := PChar(DriveLetter+':\');
szDevicePath := PChar(DriveLetter+':');
szVolumeAccessPath := PChar(Format('\\.\%s:',[DriveLetter]));
DeviceNumber:=-1;
// open the storage volume
hVolume := CreateFile(szVolumeAccessPath, 0, FILE_SHARE_READ OR FILE_SHARE_WRITE, nil, OPEN_EXISTING, 0, 0);
if (hVolume <> INVALID_HANDLE_VALUE) then
try
//get the volume's device number
dwBytesReturned := 0;
res := DeviceIoControl(hVolume, IOCTL_STORAGE_GET_DEVICE_NUMBER, nil, 0, @sdn, SizeOf(sdn), dwBytesReturned, nil);
if res then
DeviceNumber := sdn.DeviceNumber;
finally
CloseHandle(hVolume);
end;
if DeviceNumber=-1 then exit;
// get the drive type which is required to match the device numbers correctely
DriveType := GetDriveType(szRootPath);
// get the dos device name (like \device\floppy0) to decide if it's a floppy or not - who knows a better way?
QueryDosDevice(szDevicePath, szDosDeviceName, MAX_PATH);
// get the device instance handle of the storage volume by means of a SetupDi enum and matching the device number
DevInst := GetDrivesDevInstByDeviceNumber(DeviceNumber, DriveType, szDosDeviceName);
if ( DevInst = 0 ) then
exit;
VetoType := PNP_VetoTypeUnknown;
bSuccess := false;
// get drives's parent, e.g. the USB bridge, the SATA port, an IDE channel with two drives!
DevInstParent := 0;
resCM := CM_Get_Parent(DevInstParent, DevInst, 0);
for tries:=0 to 3 do // sometimes we need some tries...
begin
FillChar(VetoName[0], SizeOf(VetoName), 0);
// CM_Query_And_Remove_SubTree doesn't work for restricted users
//resCM = CM_Query_And_Remove_SubTree(DevInstParent, &VetoType, VetoNameW, MAX_PATH, CM_REMOVE_NO_RESTART); // CM_Query_And_Remove_SubTreeA is not implemented under W2K!
//resCM = CM_Query_And_Remove_SubTree(DevInstParent, NULL, NULL, 0, CM_REMOVE_NO_RESTART); // with messagebox (W2K, Vista) or balloon (XP)
resCM := CM_Request_Device_Eject(DevInstParent, @VetoType, @VetoName[0], Length(VetoName), 0);
resCM := CM_Request_Device_Eject(DevInstParent,nil, nil, 0, 0); // optional -> shows messagebox (W2K, Vista) or balloon (XP)
bSuccess := (resCM=CR_SUCCESS) and (VetoType=PNP_VetoTypeUnknown);
if ( bSuccess ) then
break;
Sleep(500); // required to give the next tries a chance!
end;
if ( bSuccess ) then
Writeln('Success')
else
Writeln('Failed');
end;
begin
try
LoadSetupApi;
LoadConfigManagerApi;
EjectUSB('F');
except
on E: Exception do
Writeln(E.ClassName, ': ', E.Message);
end;
Readln;
end.
于 2012-06-14T16:34:29.383 に答える
2
これはドライブを排出しませんが、ドライブのバッファをフラッシュし、安全に取り外せるようにします。Vista 以降 (権限が制限されたユーザー (IIRC) として実行している場合は XP) での管理者権限が必要です。が呼び出されることを確認するために、おそらく try..finally を実行する必要がありCloseHandleます。ここでは水平スクロールなしでコードのフォーマットがきついので、これは読者の演習として残します。:-)
unit USBDriveFlush;
interface
uses Windows;
type
// Taken from JEDI JwaWinIoctl
PSTORAGE_HOTPLUG_INFO = ^STORAGE_HOTPLUG_INFO;
{$EXTERNALSYM PSTORAGE_HOTPLUG_INFO}
_STORAGE_HOTPLUG_INFO = record
Size: DWORD; // version
MediaRemovable: BOOLEAN; // ie. zip, jaz, cdrom, mo, etc. vs hdd
MediaHotplug: BOOLEAN; // ie. does the device succeed a lock
// even though its not lockable media?
DeviceHotplug: BOOLEAN; // ie. 1394, USB, etc.
WriteCacheEnableOverride: BOOLEAN; // This field should not be
// relied upon because it is no longer used
end;
{$EXTERNALSYM _STORAGE_HOTPLUG_INFO}
STORAGE_HOTPLUG_INFO = _STORAGE_HOTPLUG_INFO;
{$EXTERNALSYM STORAGE_HOTPLUG_INFO}
TStorageHotplugInfo = STORAGE_HOTPLUG_INFO;
PStorageHotplugInfo = PSTORAGE_HOTPLUG_INFO;
function FlushUSBDrive(const Drive: string): Boolean;
implementation
function FlushUSBDrive(const Drive: string): Boolean;
var
shpi : TStorageHotplugInfo;
retlen : DWORD; //unneeded, but deviceiocontrol expects it
h : THandle;
begin
Result := False;
h := CreateFile(PChar('\\.\' + Drive),
0,
FILE_SHARE_READ or FILE_SHARE_WRITE,
nil,
OPEN_EXISTING,
0,
0);
if h <> INVALID_HANDLE_VALUE then
begin
shpi.Size := SizeOf(shpi);
if DeviceIoControl(h,
IOCTL_STORAGE_GET_HOTPLUG_INFO,
nil,
0,
@shpi,
SizeOf(shpi),
retlen,
nil) then
begin
//shpi now has the existing values, so you can check to
//see if the device is already hot-pluggable
if not shpi.DeviceHotplug then
begin
shpi.DeviceHotplug:= True;
//Need to use correct administrator security privilages here
//otherwise it'll just give 'access is denied' error
Result := DeviceIoControl(h,
IOCTL_STORAGE_SET_HOTPLUG_INFO,
@shpi,
SizeOf(shpi),
nil,
0,
retlen,
nil);
end;
end;
CloseHandle(h);
end;
end;
サンプル使用:
if FlushUSBDrive('G:') then
ShowMessage('Safe to remove USB drive G:')
else
ShowMessage('Flush of drive G: failed!' +
SysErrorMessage(GetLastError()));
于 2012-06-14T02:00:12.757 に答える