CreateWindow因无法查找窗口类而失败 - C++

Question

在我的应用程序中,该函数CreateWindow由于某种原因失败. GetLastError表示错误1407,根据MSDN文档,"无法找到窗口类".以下代码显示了CreateWindow在调用时如何调用以及相应的变量名称:

m_hInstance = ::GetModuleHandle( NULL );

if ( m_hInstance == NULL )
{
    TRACE(_T("CNotifyWindow::CNotifyWindow : Failed to retrieve the module handle.\r\n\tError: %d\r\n\tFile: %s\r\n\tLine: %d\r\n"), ::GetLastError(), __WFILE__, __LINE__);
    THROW(::GetLastError());
}

m_hWnd = ::CreateWindow(
    _pwcWindowClass,    // L"USBEventNotificationWindowClass"
    _pwcWindowName,     // L"USBEventNotificationWindow"
    WS_ICONIC,
    0,
    0,
    CW_USEDEFAULT,
    0,
    NULL,
    NULL,
    m_hInstance,        // 0x00400000
    NULL
    );

if ( m_hWnd == NULL )   // m_hWnd is returned as NULL and exception is thrown.
{
    TRACE(_T("CNotifyWindow::CNotifyWindow : Failed to create window.\r\n\tError: %d\r\n\tFile: %s\r\n\tLine: %d\r\n"), ::GetLastError(), __WFILE__, __LINE__);
    THROW(::GetLastError());
}

::ShowWindow( m_hWnd, SW_HIDE );

我究竟做错了什么？

Answer 1

您必须先调用RegisterClassEx,然后才能在CreateWindow上使用窗口类.

这里的示例代码.

每个进程都必须注册自己的窗口类.要注册应用程序本地类,请使用RegisterClassEx函数.您必须定义窗口过程,填充WNDCLASSEX结构的成员,然后将指向结构的指针传递给RegisterClassEx函数.