生成一个点击鼠标右键出现子对话框，点击鼠标左键没反应的m语言程序

可以使用以下 MFC 代码实现：

// 右键菜单对话框
class CRightMenuDlg : public CDialogEx
{
public:
    CRightMenuDlg(CWnd* pParent = nullptr);

    enum { IDD = IDD_RIGHTMENU_DIALOG };

protected:
    virtual void DoDataExchange(CDataExchange* pDX);

protected:
    HICON m_hIcon;

    afx_msg void OnPaint();
    afx_msg HCURSOR OnQueryDragIcon();
    afx_msg void OnRButtonDown(UINT nFlags, CPoint point);

    DECLARE_MESSAGE_MAP()
};

CRightMenuDlg::CRightMenuDlg(CWnd* pParent /*=nullptr*/)
    : CDialogEx(IDD_RIGHTMENU_DIALOG, pParent)
{
    m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void CRightMenuDlg::DoDataExchange(CDataExchange* pDX)
{
    CDialogEx::DoDataExchange(pDX);
}

BEGIN_MESSAGE_MAP(CRightMenuDlg, CDialogEx)
    ON_WM_PAINT()
    ON_WM_QUERYDRAGICON()
    ON_WM_RBUTTONDOWN()
END_MESSAGE_MAP()

void CRightMenuDlg::OnPaint()
{
    if (IsIconic())
    {
        CPaintDC dc(this); // 绘制设备上下文

        SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);

        // 中心图标
        int cxIcon = GetSystemMetrics(SM_CXICON);
        int cyIcon = GetSystemMetrics(SM_CYICON);
        CRect rect;
        GetClientRect(&rect);
        int x = (rect.Width() - cxIcon + 1) / 2;
        int y = (rect.Height() - cyIcon + 1) / 2;

        dc.DrawIcon(x, y, m_hIcon);
    }
    else
    {
        CDialogEx::OnPaint();
    }
}

HCURSOR CRightMenuDlg::OnQueryDragIcon()
{
    return static_cast<HCURSOR>(m_hIcon);
}

void CRightMenuDlg::OnRButtonDown(UINT nFlags, CPoint point)
{
    CMenu menu;
    menu.CreatePopupMenu();
    menu.AppendMenu(MF_STRING, 1, _T("子对话框"));

    menu.TrackPopupMenu(TPM_LEFTALIGN | TPM_RIGHTBUTTON, point.x, point.y, this);

    CDialogEx::OnRButtonDown(nFlags, point);
}

// 主程序
class CRightMenuApp : public CWinApp
{
public:
    CRightMenuApp();

public:
    virtual BOOL InitInstance();

    DECLARE_MESSAGE_MAP()
};

CRightMenuApp::CRightMenuApp()
{
}

CRightMenuApp theApp;

BOOL CRightMenuApp::InitInstance()
{
    CWinApp::InitInstance();

    AfxEnableControlContainer();

    CRightMenuDlg dlg;
    m_pMainWnd = &dlg;
    dlg.DoModal();

    return FALSE;
}

这个程序创建了一个 MFC 对话框窗口，当用户在窗口上点击鼠标右键时，会弹出一个子对话框。而当用户点击鼠标左键时，没有任何反应。