c++ - WM_XBUTTONDOWN return value difference between ATL/MSDN documented value? -
from https://msdn.microsoft.com/en-us/library/windows/desktop/ms646245(v=vs.85).aspx, extract that:
if application processes message, should return true. more information processing return value, see remarks section.
in case matters, same holds wm_xbuttonup , wm_xbuttondblclk.
i expected find msg_wm_xbuttondown this. however, in atlcrack.h chromium (https://src.chromium.org/svn/trunk/src/third_party/wtl/include/atlcrack.h) , find following:
// void onxbuttondown(int fwbutton, int dwkeys, cpoint ptpos) #define msg_wm_xbuttondown(func) \ if (umsg == wm_xbuttondown) \ { \ setmsghandled(true); \ func(get_xbutton_wparam(wparam), get_keystate_wparam(wparam), _wtypes_ns::cpoint(get_x_lparam(lparam), get_y_lparam(lparam))); \ lresult = 0; \ if(ismsghandled()) \ return true; \ } similar pieces can found msg_wm_xbuttondown , msg_wm_xbuttondblclk.
in snippet, line lresult = 0 confuses me. shouldn't lresult = true (according msdn)?
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