启用和禁用USB端口 [英] Enable and disable USB port

问题描述

任何人都可以告诉我如何使用C / C ++启用和禁用USB端口。

Can anyone tell me how to enable and disable USB port using C/C++.

我已经搜索了一种方法来做这个...使用Windows注册表，但有是一些问题。

I have already searched one way to do this..using windows registry but there are some problems with it.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\USBSTOR

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\USBSTOR

更改开始值的值为3 ----用于unblock
4 ----块

change the value of start value to 3----for unblock 4----block

它不会在窗口7上显示正确的行为。eg-
当我改变开始值的值为4它禁用usb端口，但再次为启用我们需要重新启动系统和一个事情，禁用所有的端口被禁用后，但仍然我们能够使用已经插入的设备

It does not show correct behavior on windows 7. eg- when I change the value of start value to 4 it disable the usb ports but again for enabling we need to restart the system and one more thing after disabling all the ports are disabled but still we are able to use already plugged device.

其他方法吗？

推荐答案

真正回答对问题的意见设备检测。

This is really answering comments on the question r.e. device detection.

在控制台应用程序中创建隐藏的窗口。

Create a hidden window in your console application.

此示例假设您有一个类 DevNotifier ，具有 HWND hidden_​​wnd _; 成员变量：

This example assumes you have a class called DevNotifier, with an HWND hidden_wnd_; member variable:

static TCHAR const        s_window_class[] = _T("Device notification window");
static TCHAR const* const s_window_title   = s_window_class;

LRESULT CALLBACK 
DevNotifierWndProc(
    HWND    hWnd, 
    UINT    message, 
    WPARAM  wParam, 
    LPARAM  lParam
) {
    DevNotifier* dn = (DevNotifier*) ::GetWindowLongPtr(hWnd, GWLP_USERDATA);
    switch (message)
    {
    case WM_DEVICECHANGE:
        dn->onWM_DEVICECHANGE(
            wParam,
            lParam
        );
    break;
    default:
        return ::DefWindowProc(hWnd, message, wParam, lParam);
    }
    return 0;
}

void
DevNotifier::createHiddenWindow()
{
        HINSTANCE hinstance = ::GetModuleHandle(NULL);

        if ((hinstance == 0) || (hinstance == INVALID_HANDLE_VALUE))
        {
            throw Exception("Failed to get application instance handle.");
        }

        // register window class

        WNDCLASSEX wcex;

        ::memset(&wcex, 0, sizeof(wcex));

        wcex.cbSize = sizeof(WNDCLASSEX);

        wcex.style          = 0;
        wcex.lpfnWndProc    = &DevNotifierWndProc;
        wcex.cbClsExtra     = 0;
        wcex.cbWndExtra     = 0;
        wcex.hInstance      = hinstance;
        wcex.hIcon          = 0;
        wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);
        wcex.hbrBackground  = 0;
        wcex.lpszMenuName   = 0;
        wcex.lpszClassName  = s_window_class;
        wcex.hIconSm        = 0;

        (void) ::RegisterClassEx(&wcex);

        // Create the window

        hidden_wnd_ = ::CreateWindow(
            s_window_class, 
            s_window_title,
            WS_POPUP,
            CW_USEDEFAULT, 
            CW_USEDEFAULT, 
            CW_USEDEFAULT, 
            CW_USEDEFAULT, 
            NULL, 
            NULL, 
            hinstance, 
            NULL
        );

        if (!hidden_wnd_) {
            throw Exception("Failed to create device notification window");
        }
    #ifdef _WIN64
        ::SetWindowLongPtr(static_cast<HWND>(hidden_wnd_), GWLP_USERDATA, (LONG_PTR)this);
    #else
        ::SetWindowLongPtr(static_cast<HWND>(hidden_wnd_), GWLP_USERDATA, (LONG)this);
    #endif
        ::ShowWindow(static_cast<HWND>(hidden_wnd_), SW_HIDE);
}

您可以在hidden_​​wnd_上注册通知。

You can register for notifications on hidden_wnd_.
e.g.

    DEV_BROADCAST_DEVICEINTERFACE filter;
    ZeroMemory(&filter, sizeof(filter));
    filter.dbcc_size = sizeof(filter);
    filter.dbcc_devicetype = DBT_DEVTYP_DEVICEINTERFACE;
    filter.dbcc_classguid = /* SOME INTERFACE GUID */;
    HDEVNOTIFY hdn = ::RegisterDeviceNotification(
        hidden_wnd_, 
        &filter, 
        DEVICE_NOTIFY_WINDOW_HANDLE
    );

您需要实现该函数来处理WM_DEVICE_CHANGE消息：

You'll need to implement the function to deal with the WM_DEVICE_CHANGE messages:

bool
DevNotifier::onWM_DEVICECHANGE(WPARAM wparam, LPARAM lparam)
{
    DEV_BROADCAST_HDR* dbh = (DEV_BROADCAST_HDR*)lparam;
    // Note dbh will NOT always be valid, depending upon the value of wparam.

    if (wparam == DBT_DEVNODES_CHANGED) {
        // Do some stuff here
        return true;
    }
    else if (wparam == DBT_DEVICEARRIVAL) {
        DEV_BROADCAST_HDR* hdr = (DEV_BROADCAST_HDR*)lparam;
        if (hdr->dbch_devicetype == DBT_DEVTYP_DEVICEINTERFACE) {
            DEV_BROADCAST_DEVICEINTERFACE* devinterface = 
                (DEV_BROADCAST_DEVICEINTERFACE*)hdr;

            // Do some stuff here
        }       
    }
    else if (wparam == DBT_DEVICEREMOVEPENDING) {
    }
    else if (wparam == DBT_DEVICEREMOVECOMPLETE) {
        HANDLE h = INVALID_HANDLE_VALUE;
        DEV_BROADCAST_HDR* phdr = (DEV_BROADCAST_HDR*) lparam;
        if (phdr->dbch_devicetype == DBT_DEVTYP_HANDLE) {
            DEV_BROADCAST_HANDLE* pdbh = (DEV_BROADCAST_HANDLE*) lparam;
            h = pdbh->dbch_handle;
        }
        else if (phdr->dbch_devicetype == DBT_DEVTYP_DEVICEINTERFACE) {
            DEV_BROADCAST_DEVICEINTERFACE* devinterface = 
                (DEV_BROADCAST_DEVICEINTERFACE*)phdr;

            // Do some stuff here
        }
        // Maybe do some stuff here too.
    }
    return false;
}

在您的控制台应用程序中，您必须运行消息泵windows消息工作。

In your console application you are going to have to run a message pump to get windows messages to work. If you have got other stuff to do while the application is waiting for messages then you'll need to also handle that here.

while (GetMessage(&message, NULL, 0, 0) > 0) {
  TranslateMessage(&message);
  DispatchMessage(&message);
}

这篇关于启用和禁用USB端口的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！