为什么会出现“ excepted a ')'”的错误，下面是代码

Question

if (this->m_hWnd = CreateWindowEx(
    0,
    this->m_szClassName.c_str(),
    this->m_szAppName.c_str(),
    WS_DLGFRAME | WS_SYSMENU | WS_MINIMIZEBOX | WS_MAXIMIZE,
    (GetSystemMetrics(SM_CXSCREEN) - _windowRC.right) / 2,
    (GetSystemMetrics(SM_CXSCREEN) - _windowRC.bottom) / 2,
    _windowRC.right, _windowRC.bottom, nullptr, nullptr, nullptr, this
);/*';' underlined in red*/ !this->m_hWnd)
    throw runtime_error("Error, can't create main window!"s);

我正在重写YouTube代码，试图弄清楚它是如何工作的，我之前写过类似的条件，但没有发生这样的错误

Answer 1

if (this->m_hWnd = CreateWindowEx(
    0,
    this->m_szClassName.c_str(),
    this->m_szAppName.c_str(),
    WS_DLGFRAME | WS_SYSMENU | WS_MINIMIZEBOX | WS_MAXIMIZE,
    (GetSystemMetrics(SM_CXSCREEN) - _windowRC.right) / 2,
    (GetSystemMetrics(SM_CXSCREEN) - _windowRC.bottom) / 2,
    _windowRC.right, _windowRC.bottom, nullptr, nullptr, nullptr, this
)

插入

); if (

!this->m_hWnd)
        throw runtime_error("Error, can't create main window!"s);

...或类似的，那就有意义了。