用c++代码写win32 做一简单窗口，添加一个“非模式对话框”菜单项，当用户点击该菜单项时，在主菜单条下添加一个弹出式菜单“对话框”，下面有菜单项，分别为“打开”、“关闭”、分隔线和“删除菜单”，初始情况下“删除菜单”为不可用

这是一个编程问题，可以直接回答。以下是一个简单的 C 代码示例，实现了一个窗口和一个非模式对话框菜单项，当用户点击该菜单项时，在主菜单条下添加一个弹出式菜单“对话框”，包含“打开”、“关闭”和“删除菜单”菜单项，初始情况下“删除菜单”为不可用。

#include <windows.h>

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    // Register the window class
    const char CLASS_NAME[] = "Sample Window Class";

    WNDCLASS wc = {0};

    wc.lpfnWndProc   = WndProc;
    wc.hInstance     = hInstance;
    wc.lpszClassName = CLASS_NAME;

    RegisterClass(&wc);

    // Create the window
    HWND hWnd = CreateWindowEx(
        0,                              // Optional window styles
        CLASS_NAME,                     // Window class
        "Sample Window",                // Window text
        WS_OVERLAPPEDWINDOW,            // Window style

        // Size and position
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,

        NULL,       // Parent window
        NULL,       // Menu
        hInstance,  // Instance handle
        NULL        // Additional application data
        );

    if (hWnd == NULL)
    {
        return 0;
    }

    // Show the window
    ShowWindow(hWnd, nCmdShow);

    // Run the message loop
    MSG msg = {0};

    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 HMENU hPopupMenu = NULL;
    static BOOL bMenuEnabled = FALSE;

    switch (message)
    {
        case WM_CREATE:
        {
            // Create the popup menu
            hPopupMenu = CreatePopupMenu();
            AppendMenu(hPopupMenu, MF_STRING, ID_OPEN, "打开");
            AppendMenu(hPopupMenu, MF_STRING, ID_CLOSE, "关闭");
            AppendMenu(hPopupMenu, MF_SEPARATOR, 0, NULL);
            AppendMenu(hPopupMenu, MF_STRING | MF_DISABLED, ID_DELETE, "删除菜单");

            return 0;
        }

        case WM_COMMAND:
        {
            switch (LOWORD(wParam))
            {
                case ID_DIALOG:
                {
                    // Add the popup menu to the main menu
                    HMENU hMenu = GetMenu(hWnd);
                    if (hMenu != NULL)
                    {
                        InsertMenu(hMenu, -1, MF_BYPOSITION | MF_POPUP, (UINT_PTR)hPopupMenu, "对话框");
                        bMenuEnabled = TRUE;
                        EnableMenuItem(hPopupMenu, ID_DELETE, MF_ENABLED);
                        DrawMenuBar(hWnd);
                    }

                    return 0;
                }

                case ID_OPEN:
                {
                    // Handle the "打开" menu item
                    MessageBox(hWnd, "打开", "提示", MB_OK);
                    return 0;
                }

                case ID_CLOSE:
                {
                    // Handle the "关闭" menu item
                    MessageBox(hWnd, "关闭", "提示", MB_OK);
                    return 0;
                }

                case ID_DELETE:
                {
                    // Handle the "删除菜单" menu item
                    HMENU hMenu = GetMenu(hWnd);
                    if (hMenu != NULL)
                    {
                        RemoveMenu(hMenu, -1, MF_BYPOSITION);
                        bMenuEnabled = FALSE;
                        EnableMenuItem(hPopupMenu, ID_DELETE, MF_DISABLED | MF_GRAYED);
                        DrawMenuBar(hWnd);
                    }

                    return 0;
                }
            }

            break;
        }

        case WM_DESTROY:
        {
            // Destroy the popup menu
            DestroyMenu(hPopupMenu);

            PostQuitMessage(0);
            return 0;
        }
    }

    return DefWindowProc(hWnd, message, wParam, lParam);
}