c - C语言的设备通知程序

Question

我用c语言编写了这段代码，用于检测win xp 32中的闪存 但它没有做任何事情 谁能帮忙 (我只想了解何时插入闪存然后运行另一个程序，但我需要一个 wndmain 和一个 wndproc，但我无法正确编写它们) 最后一个问题是它可能不起作用，因为我在 win 7 64 位中运行它？？？

#include <stdio.h>
#include <tchar.h>
#include <windows.h>
#include <dbt.h>
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine,
                   int nCmdShow)
{
    hInstance =(HINSTANCE)(GetModuleHandle(NULL));
    if(WndProc)
    {

    MSG msg;
    while( GetMessage(&msg, NULL, 0, 0) > 0 )
    {
         TranslateMessage(&msg);
          DispatchMessage(&msg);
          printf("%s" , msg);
    }

    }
    return 0;
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT uiMsg, WPARAM wParam, LPARAM lParam)
{
    if (uiMsg == WM_DEVICECHANGE)
    {
        MessageBox(NULL, TEXT("WM_DEVICECHANGE"), TEXT("WndProc"), MB_OK);
        return 0;
    }
    return DefWindowProc(hWnd, uiMsg, wParam, lParam);
}

Answer 1

您可能可以创建一个预定义窗口类型的实例，然后对其进行子类化(将其窗口过程设置为您编写的窗口过程)，这将提供比我编写的代码更短的代码展示。您应该注意，您链接到的 MSDN 代码仅提供代码片段，也就是说 - 这是一个不完整的程序。您仍然需要有一种从 Windows 接收消息的机制。

这是一个在win7下捕获插入和删除消息的程序，用minGW编译。只需将 13 行添加到 code::blocks 内的 Win32 Gui(框架应用程序)模板中即可。

#include <windows.h>
#include <dbt.h>

//  Declare Windows procedure
LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM);

//  Make the class name into a global variable
char szClassName[ ] = "CodeBlocksWindowsApp";

int WINAPI WinMain (HINSTANCE hThisInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR lpszArgument,
                     int nCmdShow)
{
    HWND hwnd;               // This is the handle for our window
    MSG messages;            // Here messages to the application are saved
    WNDCLASSEX wincl;        // Data structure for the windowclass

    // The Window structure
    wincl.hInstance = hThisInstance;
    wincl.lpszClassName = szClassName;
    wincl.lpfnWndProc = WindowProcedure;      /* This function is called by windows */
    wincl.style = CS_DBLCLKS;                 /* Catch double-clicks */
    wincl.cbSize = sizeof (WNDCLASSEX);

    /* Use default icon and mouse-pointer */
    wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION);
    wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
    wincl.hCursor = LoadCursor (NULL, IDC_ARROW);
    wincl.lpszMenuName = NULL;                 /* No menu */
    wincl.cbClsExtra = 0;                      /* No extra bytes after the window class */
    wincl.cbWndExtra = 0;                      /* structure or the window instance */
    /* Use Windows's default colour as the background of the window */
    wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND;

    /* Register the window class, and if it fails quit the program */
    if (!RegisterClassEx (&wincl))
        return 0;

    /* The class is registered, let's create the program*/
    hwnd = CreateWindowEx (
           0,                   /* Extended possibilites for variation */
           szClassName,         /* Classname */
           "Code::Blocks Template Windows App",       /* Title Text */
           WS_OVERLAPPEDWINDOW, /* default window */
           CW_USEDEFAULT,       /* Windows decides the position */
           CW_USEDEFAULT,       /* where the window ends up on the screen */
           544,                 /* The programs width */
           375,                 /* and height in pixels */
           HWND_DESKTOP,        /* The window is a child-window to desktop */
           NULL,                /* No menu */
           hThisInstance,       /* Program Instance handler */
           NULL                 /* No Window Creation data */
           );

    /* Make the window visible on the screen */
    ShowWindow (hwnd, nCmdShow);

    /* Run the message loop. It will run until GetMessage() returns 0 */
    while (GetMessage (&messages, NULL, 0, 0))
    {
        /* Translate virtual-key messages into character messages */
        TranslateMessage(&messages);
        /* Send message to WindowProcedure */
        DispatchMessage(&messages);
    }

    /* The program return-value is 0 - The value that PostQuitMessage() gave */
    return messages.wParam;
}


/*  This function is called by the Windows function DispatchMessage()  */

LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    UINT event;

    switch (message)                  /* handle the messages */
    {
        case WM_DESTROY:
            PostQuitMessage (0);       /* send a WM_QUIT to the message queue */
            break;
        case WM_DEVICECHANGE:
            event = (UINT)wParam;
            switch (event)
            {
                case DBT_DEVICEARRIVAL:
                    MessageBox(NULL, "Device arrival", "Notice", MB_ICONASTERISK);
                    break;

                case DBT_DEVICEREMOVECOMPLETE:
                    MessageBox(NULL, "Device removal", "Notice", MB_ICONASTERISK);
                    break;
            }
            break;
        default:                      /* for messages that we don't deal with */
            return DefWindowProc (hwnd, message, wParam, lParam);
    }
    return 0;
}

更新: 将以下 WindowProcedure 与之前链接到的 MSDN 代码 mellodi 结合使用。这将允许检索设备名称和其他属性(我完全忽略了)

LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    UINT event;

    switch (message)                  /* handle the messages */
    {
        case WM_DESTROY:
            PostQuitMessage (0);       /* send a WM_QUIT to the message queue */
            break;
        case WM_DEVICECHANGE:
                Main_OnDeviceChange(hwnd, wParam, lParam);
            break;
        default:                      /* for messages that we don't deal with */
            return DefWindowProc (hwnd, message, wParam, lParam);
    }
    return 0;
}