Re: MSHTML IWebBrowser2 problem - Catching events causes missed keystrokes

"Scot T Brennecke" <>
Sat, 30 May 2009 18:39:51 -0500
Since this question relates to the use of MFC, why did you ask in the ATL newsgroup?

<> wrote in message
I've got a bit of a problem with my application using MSHTML.
Everything works except the odd keystroke gets missed typing fast. I
think it may have to do with sinking the events, like the system is
getting bogged down passing events around and then misses keyboard

The details: my application is a separate program written in C++ and
MFC in Visual Studio 2005. The program attaches to a currently running
(independent) instance of Internet Explorer, so the programs are in
two seperate processes/threads. My program gets a pointer to the
IWebBrowser2 interface of each tab and passes it to an corresponding
object of type CCmdTarget:

class CHandler : public CCmdTarget
  IWebBrowser2* m_pWebBrowser2;
  DWORD m_dwBrowserCookie;

This class keeps track of what's happening in the browser page. I sink
the browser events with the following command in CHandler:

LPUNKNOWN pUnkSink = GetIDispatch(FALSE);
retval = AfxConnectionAdvise((LPUNKNOWN)m_pWebBrowser2,
DIID_DWebBrowserEvents2, pUnkSink, FALSE, &m_dwBrowserCookie);

If I comment out the AfxConnectionAdvise, then no keystrokes are
missed but no more events are caught. If I leave the line in then I
correctly sink the events but miss the occasional keystroke if typing

Someone suggested marshalling may be the problem between the two
threads (mine and IE) but I'm not sure A) how to do that, and B) why
it would work _almost_ fine without it.

Any suggestions are greatly appreciated!

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