How do I send windows messages to a MessageBox - c++

Question

I'm looking for a way to manipulate a MessageBox like a window, would I have to actually use CreateWindowEx and make a tiny window in order to get the full functionality of a window including using things such as WM_GETTEXT and WM_SETTEXT or is there some way I can send these messages to a MessageBox? If I absolutely can't send windows messages to a MessageBox, then is there alternate methods less complicated then using CreateWindowEx to accomplish what I'm looking for?

Answer 1

Use a thread-local WH_CBT hook when you call MessageBox() to get its window handle. You can then send messages to it like any other window.
// if you need to customize MessageBox() across threads,
// store this variable in a TLS (thread-local storage) slot...
HHOOK hHook;
LRESULT CALLBACK MyCBTHook(int nCode, WPARAM wParam, LPARAM lParam)
{
switch (nCode)
{
case HCBT_CREATEWND: // window is being created
case HCBT_ACTIVATE: // window is being activated
{
HWND hWnd = (HWND) wParam;
// use hWnd as needed...
break;
}
}
return CallNextHookEx(hHook);
}
int MyMessageBox(HWND hWnd, LPCTSTR lpText, LPCTSTR lpCaption, UINT uType)
{
hHook = SetWindowsHookEx(WH_CBT, (HOOKPROC)&MyCBTHook, NULL, GetCurrentThreadId());
int iResult = MyMessageBox(hWnd, lpText, lpCaption, uType);
UnhookWindowsHookEx(hHook);
return iResult;
}