为什么窗口不显示菜单呢？
#include <windows.h>#include "resource.h"#define ID_TIMER 1LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;TCHAR szAppName[] = TEXT ("MenuDemo") ;int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow){ HWND hwnd ; MSG msg ; WNDCLASS wndclass ; wndclass.style = CS_HREDRAW | CS_VREDRAW ; wndclass.lpfnWndProc = WndProc ; wndclass.cbClsExtra = 0 ; wndclass.cbWndExtra = 0 ; wndclass.hInstance = hInstance ; wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ; wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ; wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ; wndclass.lpszMenuName = szAppName ; wndclass.lpszClassName = szAppName ; if (!RegisterClass (&wndclass)) { MessageBox (NULL, TEXT ("This program requires Windows NT!"), szAppName, MB_ICONERROR) ; return 0 ; } hwnd = CreateWindow (szAppName, TEXT ("Menu Demonstration"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL) ; ShowWindow (hwnd, iCmdShow) ; UpdateWindow (hwnd) ; while (GetMessage (&msg, NULL, 0, 0)) { TranslateMessage (&msg) ; DispatchMessage (&msg) ; } return msg.wParam ;}LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam){ static int idColor[5] = {WHITE_BRUSH, LTGRAY_BRUSH, GRAY_BRUSH, DKGRAY_BRUSH, BLACK_BRUSH}; static int iSelection = IDM_BKGND_WHITE; HMENU hMenu; switch(message) { case WM_COMMAND: hMenu = GetMenu(hwnd); switch(LOWORD(wParam)) { case IDM_FILE_NEW: case IDM_FILE_OPEN: case IDM_FILE_SAVE: case IDM_FILE_SAVE_AS: MessageBeep (0) ; return 0 ; case IDM_APP_EXIT: SendMessage(hwnd, WM_CLOSE, 0, 0); return 0; case IDM_EDIT_UNDO: case IDM_EDIT_CUT: case IDM_EDIT_COPY: case IDM_EDIT_PASTE: case IDM_EDIT_CLEAR: MessageBeep (0) ; return 0 ; case IDM_BKGND_WHITE: // Note: Logic below case IDM_BKGND_LTGRAY: // assumes that IDM_WHITE case IDM_BKGND_GRAY: // through IDM_BLACK are case IDM_BKGND_DKGRAY: // consecutive numbers in case IDM_BKGND_BLACK: CheckMenuItem(hMenu, iSelection, MF_UNCHECKED); iSelection = LOWORD(wParam); CheckMenuItem(hMenu, iSelection, MF_CHECKED); SetClassLong(hwnd,GCL_HBRBACKGROUND, (LONG) GetStockObject(idColor[LOWORD(wParam)] - IDM_BKGND_WHITE)); InvalidateRect(hwnd, NULL, TRUE); case IDM_TIMER_START: if (SetTimer(hwnd, ID_TIMER, 1000, NULL)) { EnableMenuItem(hMenu, IDM_TIMER_START, MF_GRAYED); EnableMenuItem(hMenu, IDM_TIMER_STOP, MF_ENABLED); } return 0; case IDM_TIMER_STOP: KillTimer(hwnd, ID_TIMER); EnableMenuItem(hMenu, IDM_TIMER_START, MF_ENABLED); EnableMenuItem(hMenu, IDM_TIMER_STOP, MF_GRAYED); return 0; case IDM_APP_HELP: MessageBox(hwnd, TEXT("Help not yet implemented!"), szAppName, MB_ICONINFORMATION | MB_OK); return 0; } break; case WM_TIMER: MessageBeep(0); return 0; case WM_DESTROY: PostQuitMessage(0); return 0; } return DefWindowProc(hwnd, message, wParam, lParam); }