Alexander Eisenhuth schrieb: > Hello list, > > I'm having a problem with a python COM Excel client that rarely gets the > exception pywintypes.com_error with the error code -2147417846. (means Excel > is > busy) Here the python code of the exception handling: > > [...] > try: > # write a excel cell > [...] > except pywintypes.com_error, ex: > if ex[0] == -2147417846: > time.sleep(1.0) > # retry write? > [...] > > My first approach was to retry the writing to the excel cell. But that ends > in a > hanging Excel application (probably a deadlock). > > After a little research I found this post: > > http://social.msdn.microsoft.com/Forums/en-US/vsto/thread/70ef972b-51b6-4ece-a4af-d6b4e111eea5 > > "[...] If you don't register a MessageFilter yourself (by calling > CoRegisterMessageFilter), you will get default behavior which will be to fail > the call if it gets rejected. .Net converts the failure HRESULT to an > exception. To deal with the possibility of the server being busy when you > try > to call, you need to implement IMessageFilter::RetryRejectedCall in your > client > code and also register the message filter. In most cases, you will just need > to > wait for a few seconds and then retry the call--generally that will be > sufficient time to enable Word to finish whatever it is doing so it can > handle > your call. However, if the instance of Word that you are controlling could > possibly visible, you might want to add additional logic to display the > OLEUIBUSY dialog after some amount of time has passed to notify the user that > you are waiting on Word to do something and give them the opportunity to help > the process. For example, as Misha mentions, Word will reject all incoming > calls if a modal dialog box is up. Therefore, in that situation, you would > be > blocked indefinitely until the dialog is dismissed. [...]" > > As this part of the COM API (IMessageFilter, CoRegisterMessageFilter) isn't > included in pywin32 I don't see a possibility to do that, or?
If it is really possible to do this on the client side, you can try to implement the message filter and call CoRegisterMessageFilter with comtypes. > Did anybody else have to deal with that problem? Yes, we had this in our company with MFC applications. Fortunately, these were our own and we 'fixed' them by implementing a message filter inside the applications, on the server side. -- Thomas _______________________________________________ python-win32 mailing list python-win32@python.org http://mail.python.org/mailman/listinfo/python-win32
