SDK模态对话框不能接收WM_KEYDOWN的解决方法

// main.cpp : Defines the entry point for the application./// 验证 : SDK模态对话框不能接收WM_KEYDOWN的解决方法/// 非模态对话框 + 自己做消息循环#include "stdafx.h"#include <assert.h>#include "resource.h"#define MAX_LOADSTRING 100// Global Variables:HINSTANCE hInst;// current instanceTCHAR szTitle[MAX_LOADSTRING];// The title bar textTCHAR szWindowClass[MAX_LOADSTRING];// The title bar textHACCEL g_hAccelTable = NULL;// Foward declarations of functions included in this code module:ATOMMyRegisterClass(HINSTANCE hInstance);BOOLInitInstance(HINSTANCE, int);LRESULT CALLBACKWndProc(HWND, UINT, WPARAM, LPARAM);BOOL CALLBACKDlgProcAbout(HWND, UINT, WPARAM, LPARAM);int APIENTRY WinMain(HINSTANCE hInstance,                     HINSTANCE hPrevInstance,                     LPSTR     lpCmdLine,                     int       nCmdShow){ // TODO: Place code here.MSG msg;// Initialize global stringsLoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);LoadString(hInstance, IDC_MAIN, szWindowClass, MAX_LOADSTRING);MyRegisterClass(hInstance);// Perform application initialization:if (!InitInstance (hInstance, nCmdShow)) {return FALSE;}g_hAccelTable = LoadAccelerators(hInstance, (LPCTSTR)IDC_MAIN);// Main message loop:while (GetMessage(&msg, NULL, 0, 0)) {        if (WM_KEYDOWN == msg.message) {            int bp = 0;        }if (!TranslateAccelerator(msg.hwnd, g_hAccelTable, &msg)) {TranslateMessage(&msg);DispatchMessage(&msg);}}return msg.wParam;}////  FUNCTION: MyRegisterClass()////  PURPOSE: Registers the window class.////  COMMENTS:////    This function and its usage is only necessary if you want this code//    to be compatible with Win32 systems prior to the 'RegisterClassEx'//    function that was added to Windows 95. It is important to call this function//    so that the application will get 'well formed' small icons associated//    with it.//ATOM MyRegisterClass(HINSTANCE hInstance){WNDCLASSEX wcex;wcex.cbSize = sizeof(WNDCLASSEX); wcex.style= CS_HREDRAW | CS_VREDRAW;wcex.lpfnWndProc= (WNDPROC)WndProc;wcex.cbClsExtra= 0;wcex.cbWndExtra= 0;wcex.hInstance= hInstance;wcex.hIcon= LoadIcon(hInstance, (LPCTSTR)IDI_MAIN);wcex.hCursor= LoadCursor(NULL, IDC_ARROW);wcex.hbrBackground= (HBRUSH)(COLOR_WINDOW+1);wcex.lpszMenuName= (LPCSTR)IDC_MAIN;wcex.lpszClassName= szWindowClass;wcex.hIconSm= LoadIcon(wcex.hInstance, (LPCTSTR)IDI_SMALL);return RegisterClassEx(&wcex);}////   FUNCTION: InitInstance(HANDLE, int)////   PURPOSE: Saves instance handle and creates main window////   COMMENTS:////        In this function, we save the instance handle in a global variable and//        create and display the main program window.//BOOL InitInstance(HINSTANCE hInstance, int nCmdShow){   HWND hWnd;   hInst = hInstance; // Store instance handle in our global variable   hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);   if (!hWnd)   {      return FALSE;   }   ShowWindow(hWnd, nCmdShow);   UpdateWindow(hWnd);   return TRUE;}////  FUNCTION: WndProc(HWND, unsigned, WORD, LONG)////  PURPOSE:  Processes messages for the main window.////  WM_COMMAND- process the application menu//  WM_PAINT- Paint the main window//  WM_DESTROY- post a quit message and return////LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){    int wmId, wmEvent;    int bp = 0;    PAINTSTRUCT ps;    HDC hdc;    HWND hWndDlg;    MSG msg;    TCHAR szHello[MAX_LOADSTRING];    LoadString(hInst, IDS_HELLO, szHello, MAX_LOADSTRING);        switch (message)     {    case WM_COMMAND:        wmId    = LOWORD(wParam);         wmEvent = HIWORD(wParam);         // Parse the menu selections:        switch (wmId)        {        case IDM_ABOUT:            {                // creates a modal dialog box                hWndDlg = CreateDialog(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, (DLGPROC)DlgProcAbout);                ShowWindow(hWndDlg, SW_SHOW);                UpdateWindow(hWndDlg);                while (GetMessage(&msg, NULL, 0, 0)) { ///< 参数2必须是NULL                    if (msg.message == WM_KEYDOWN) {                        bp = bp;                    }                    if (!TranslateAccelerator(msg.hwnd, g_hAccelTable, &msg)) {                        if (IsDialogMessage(msg.hwnd, &msg)) {                            /// ! 是向hWndDlg发消息，不是向 msg.hwnd                            SendMessage(hWndDlg, msg.message, msg.wParam, msg.lParam);                        } else {                            TranslateMessage(&msg);                            DispatchMessage(&msg);                        }                    }                }                bp = bp;            }            break;        case IDM_EXIT:            DestroyWindow(hWnd);            break;        default:            return DefWindowProc(hWnd, message, wParam, lParam);        }        break;        case WM_PAINT:            hdc = BeginPaint(hWnd, &ps);            // TODO: Add any drawing code here...            RECT rt;            GetClientRect(hWnd, &rt);            DrawText(hdc, szHello, strlen(szHello), &rt, DT_CENTER);            EndPaint(hWnd, &ps);            break;        case WM_DESTROY:            PostQuitMessage(0);            break;        default:            return DefWindowProc(hWnd, message, wParam, lParam);    }    return 0;}// Mesage handler for about box.BOOL CALLBACK DlgProcAbout(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam){    BOOL bRc = TRUE;    int bp = 0;    switch (message)    {    case WM_KEYDOWN:         {            bp = bp; ///< 现在可以进来了        }        break;            case WM_INITDIALOG:        bRc = TRUE;        break;    case WM_CLOSE:        DestroyWindow(hDlg);        break;    case WM_DESTROY:        PostMessage(hDlg, WM_QUIT, 0, 0);        break;    default:        bRc= FALSE;        break;    }        /// ! can't call DefWindowProc    return bRc;}