m_AnimateCtrl.Create(WS_CHILD|WS_VISIBLE,rect,this,0);
----

I want use this function my DLL file's dialogbox.
But I could not use "this".
when i use "this" there are happened compile error.
so I use GetSafeHwnd() function.

m_AnimateCtrl.Create(WS_CHILD|WS_VISIBLE,rect,(CWnd *)GetSafeHwnd(),0);
then there aren't happened compile error.
but I can't executed dll file.
Good luck.
thank you for reading it.