FindWindow( ... ) 不是 'finding' 创建的消息 window

Question

在我的代码中，我有一条消息 class，我想从另一个进程 'Find'。

class MyWindow : public CWnd
{
public:
  MyWindow::MyWindow(LPCTSTR pszClassName)
  {
    auto wcn = ::AfxRegisterWndClass(NULL);
    auto created = this->CreateEx(0, wcn, pszClassName, 0, 0, 0, 0, 0, HWND_MESSAGE, 0);
  }
};

然后在我的主应用中的某个地方。

...
auto pszClassName = _T("MyWindowClass");
auto wnd = new MyWindow(pszClassName);

auto p = FindWindow(pszClassName, nullptr); // = nullptr

// or using FindWindowExW( ... )
p = FindWindowExW(nullptr, nullptr, pszClassName, nullptr);// = nullptr
p = FindWindowExW(HWND_MESSAGE, nullptr, pszClassName, nullptr);// = nullptr

所以，无论我做什么，我似乎从来没有 'Find' 创建 window。

如何使用 FindWindow[Ex]

创建可以 'Found' 的 window

Answer 1

我正在使用 VS2013 控制台应用程序。我稍微修改了您的代码以创建一个普通的 window 和一个仅消息 window 并通过 class 名称找到它们的句柄。

输出：

Normal window=00000000003A06FE Message-only window=00000000001F06CA
FindWindow=00000000003A06FE
FindWindowEx=00000000003A06FE
FindWindowEx(HWND_MESSAGE,...)=00000000001F06CA

代码：

typedef std::basic_string<TCHAR> tstring;

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

class MyWindow //: public CWnd
{
public:
    tstring className;
    HWND hwnd;
    HWND hwndMsgOnly;
    HWND find1;
    HWND find2;
    HWND find3;

    MyWindow::MyWindow(LPCTSTR pszClassName)
    {
        className = pszClassName;

        //auto wcn = ::AfxRegisterWndClass(NULL);
        //auto created = this->CreateEx(0, wcn, pszClassName, 0, 0, 0, 0, 0, HWND_MESSAGE, 0);

        // For a console app, `hInstance` is the instance of the program
        HINSTANCE hInstance = GetModuleHandle(0);

        WNDCLASSEX windowClass;
        windowClass.lpszClassName = pszClassName;
        windowClass.cbClsExtra = NULL;
        windowClass.cbWndExtra = NULL;
        windowClass.cbSize = sizeof(WNDCLASSEX);
        windowClass.hbrBackground = (HBRUSH)CreateSolidBrush(RGB(150, 0, 0));
        windowClass.hCursor = LoadCursor(NULL, IDC_ARROW);
        windowClass.hIcon = LoadIcon(NULL, MAKEINTRESOURCE(IDI_APPLICATION));
        windowClass.hIconSm = (HICON)LoadImage(NULL, MAKEINTRESOURCE(IDI_APPLICATION), IMAGE_ICON, 16, 16, NULL);
        windowClass.hInstance = hInstance;
        windowClass.lpfnWndProc = WindowProc;
        windowClass.lpszMenuName = NULL;
        windowClass.style = CS_VREDRAW | CS_HREDRAW;
        RegisterClassEx(&windowClass);
        hwnd = CreateWindowEx(NULL, pszClassName, _T("Basic Window"), WS_OVERLAPPEDWINDOW | WS_VISIBLE, 100, 100, 500, 500, NULL, NULL, hInstance, NULL);
        hwndMsgOnly = CreateWindowEx(NULL, pszClassName, _T("Dummy name"), 0, 0, 0, 0, 0, HWND_MESSAGE, NULL, NULL, NULL);
    }
};

void window_test(MyWindow & wnd)
{
    LPCTSTR pszClassName = wnd.className.c_str();
    wnd.find1 = FindWindow(pszClassName, nullptr); // = nullptr for OP version; okay for this version

    // or using FindWindowExW( ... )
    /**
        HWND hwndParent is a handle to the parent window whose child windows are to be searched.
        If hwndParent is NULL, the function uses the desktop window as the parent window.The function searches among windows that are child windows of the desktop.
        If hwndParent is HWND_MESSAGE, the function searches all message-only windows.
    **/
    HWND hWndParent = nullptr;
    wnd.find2 = FindWindowExW(hWndParent, nullptr, pszClassName, nullptr);// = nullptr for OP version; okay for this version
    hWndParent = HWND_MESSAGE;
    wnd.find3 = FindWindowExW(hWndParent, nullptr, pszClassName, nullptr);// = nullptr for OP version; finds the message-only window in this version
}

void main()
{
    MyWindow wnd(_T("test_window"));
    cout << "Normal window=" << wnd.hwnd << " Message-only window=" << wnd.hwndMsgOnly << endl;
    window_test(wnd);
    cout << "FindWindow=" << wnd.find1 << endl;
    cout << "FindWindowEx=" << wnd.find2 << endl;
    cout << "FindWindowEx(HWND_MESSAGE,...)=" << wnd.find3 << endl;
}

FindWindow( ... ) 不是 'finding' 创建的消息 window

FindWindow( ... ) is not 'finding' created message window

c++

windows

c++11

findwindow

findwindowex