请教一个设备操作的问题

[yashi]

如果一个外部设备（比如我自己做的一个USB接口的设备）在我的应用程序运行中被拔下，那我显然要对此做处理，但是在这种情况下，系统发送的是什么消息呢？？重新插上的时候又会发送什么消息呢？谢谢！！

[isdong]

C++]
Because universal serial bus (USB) devices can be added to and removed from the system without rebooting, you might want your application to be able to respond to a new configuration of input devices. For example, you might allow a new player to join a game in progress by plugging in another controller.

To receive a message when a device is changed, you must first register for notification, as in the following code example:

PVOID hNotifyDevNode;

void RegisterForDevChange(HWND hDlg, PVOID *hNotifyDevNode)
{
DEV_BROADCAST_DEVICEINTERFACE *pFilterData =
(DEV_BROADCAST_DEVICEINTERFACE*)
_alloca(sizeof(DEV_BROADCAST_DEVICEINTERFACE));
ASSERT (pFilterData);

ZeroMemory(pFilterData, sizeof(DEV_BROADCAST_DEVICEINTERFACE));

pFilterData->dbcc_size = sizeof(DEV_BROADCAST_DEVICEINTERFACE);
pFilterData->dbcc_devicetype = DBT_DEVTYP_DEVICEINTERFACE;
pFilterData->dbcc_classguid = GUID_CLASS_INPUT;

*hNotifyDevNode = RegisterDeviceNotification(hDlg, pFilterData,
DEVICE_NOTIFY_WINDOW_HANDLE);
}
Then, in your main window procedure, check for messages announcing that a device has been attached, is about to be removed, or has been removed, as follows:

MyWindowProc(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam)
{
switch (nMsg)
{
case WM_DEVICECHANGE:
{
switch (wParam)
{
case DBT_DEVICEARRIVAL:
// Handle device arrival
break;

case DBT_DEVICEQUERYREMOVE:
// Handle device removal request
break;

case DBT_DEVICEREMOVECOMPLETE:
// Handle device removal
break;
}
}
.
.
.
}
}

[carbon107]

你是否是通过DeviceIoControl这个函数来做判断呢，
HostControllerHandle = CreateFile( "\\\\.\\HCD1",GENERIC_WRITE|GENERIC_READ,FILE_SHARE_WRITE|FILE_SHARE_READ, 0,OPEN_EXISTING,0,0);

Success = DeviceIoControl(HostControllerHandle, IOCTL_GET_HCD_DRIVERKEY_NAME, &UnicodeName,sizeof(UnicodeName),&UnicodeName, sizeof(UnicodeName), &BytesReturned, NULL);
Success决定成功与否

对于发送什么消息楼上的代码就是了