C++ MessageBox 定时关闭

定时关闭MessageBox
MessageBoxTimeout是一个微软未公开的Windows API函数。实现定时消息，功能类似于MessageBox。如果用户不回应，能定时关闭消息框。函数由user32.dll导出，windows2000及以下没有此函数。
直接上代码啦~

#include 

int DU_MessageBoxTimeout(HWND hWnd, const WCHAR* sText, const WCHAR* sCaption, UINT uType, DWORD dwMilliseconds)
{
    // Displays a message box, and dismisses it after the specified timeout.
    typedef int(__stdcall* MSGBOXWAPI)(IN HWND hWnd, IN LPCWSTR lpText, IN LPCWSTR lpCaption, IN UINT uType, IN WORD wLanguageId, IN DWORD dwMilliseconds);

    int iResult;

    HMODULE hUser32 = LoadLibraryW(L"user32.dll");
    if (hUser32)
    {
        auto MessageBoxTimeoutW = (MSGBOXWAPI)GetProcAddress(hUser32, "MessageBoxTimeoutW");

        iResult = MessageBoxTimeoutW(hWnd, sText, sCaption, uType, 0, dwMilliseconds);

        FreeLibrary(hUser32);
    }
    else {
        iResult = MessageBoxW(hWnd, sText, sCaption, uType);         // oups, fallback to the standard function!
    }
    return iResult;
}

int main()
{
	// Timeout MessageBox
    DU_MessageBoxTimeout(nullptr, L"PAUSE", L"Pause", MB_OK | MB_IConERROR | MB_SETFOREGROUND, 10000);

	// Normal MessageBox
	HMODULE user32 = LoadLibraryW(L"user32.dll");
	if (user32) {
		decltype(MessageBoxW)* messageBoxW =
			(decltype(MessageBoxW)*)GetProcAddress(user32, "MessageBoxW");
		
		if (messageBoxW) {
			messageBoxW(nullptr, L"PAUSE AGAIN", L"Pause",
				MB_OK | MB_IConERROR | MB_SETFOREGROUND);
		}
		
		FreeLibrary(user32);
	}
    return 0；
}