I have a dual idispatch interface of documentwindow class, related to powerpoint. Application which you can then use to obtain itypeinfo, itypelib pointers to enumerate all the stuff. When you implement one or more userdefined interfaces in a class, visual basic provides an implementation of queryinterface that allows clients to move among interface references. You can tell whether the query failed by checking for a null pointer, but you cannot determine why it fails. Youll soon see a version of this function that calls queryinterface. Autodesk understands that working remotely can be challenging. The next line will always have a successful hr value because it comes from the previous success already checked and not from the queryinterface call. The ccomptr class defines three assignment operators. Errorchecking routine that performs manual lifetime management of a com. The following functions both do the same logical operations. The idispatch interface performs its own release, so the code above calls release twice, the first time explicitly through the call dispatchrelease and the second time implicitly at the. However, the second version may be less errorprone because it uses the ccomptr class. Hresult axgetidispatchofobjectacdbobjectid id, idispatch ppdisp, idispatch papp.
To report problems encountered with the web help interface and. The problem here is that if the idispatch is null then the hr is never set by the line that fetches the irequest pointer. I know very little about com and nothing about atl but my guess is that you can just declare a ihtmldocument2 pdoc instead of the ccomptr spdoc because ccomptr is a pointer wrapper. Todays little program demonstrates how you can manipulate the positions of desktop icons. This means that you need to add extra python code to do a queryinterface in order to get a dynamic object where you can call the methods. When a create a new email message using automation outlook will crash if i try to request. Find answers to ihtmlelement and ihtmlelementcollection from the expert community at experts exchange. This code does not work for internet explorer versions 5. Because ccomptr and ccomqiptr do not hide calls to addref and release, this blind conversion causes a problem when the release is called through the dispatch smart pointer. Heres an abbreviated version of ccomptr showing its most important parts. The constructor doesnt save the hresult from a failed queryinterface call. I recently found an article called capture an html document as an image. This is what ccomptr is helping you with, which is a smartpointer and provides auto release of objects.
A visual basic object automatically implements queryinterface. Ccomqiptr adds a little more smarts by associating a guid for use as the interface id with a smart pointer. That page actually recommends queryinterfaceing into a ccomptr, where you get an hresult stating what failed, over using ccomqiptr, where you always get nullptr and you have no idea why interface not implemented. Returns true if the connection was successful or false if the connection failed. As in the case of addref and release, the visual basic implementation of queryinterface is fairly straightforward, but you can never see it. Api help english only 2018 sp05 to disable web help from within solidworks and use local help instead, click help use solidworks web help.
Do you have questions about working remotely or collaborating while using autodesk products. Mfc supports idispatch and com aggregation, you dont have to do a lot to get those features up and running. Your question is better, but apparently nobody knows the answer or nobody wants to explain it. Ccomptr is a convenient smart pointer atl class to manage reference counting of com objects.
For deeper understanding of connection points i suggest you read code projectcom dcom connection points and asynchronous calls part i. You can rate examples to help us improve the quality of examples. I need a class to run my version of queryinterface. Python for windows extensions old feature requests new. Ok, how can i use queryinterface to get the idispatch pointer from an iunknown pointer. The class is wizard generated, and inherits from idispatch. Find out how to get set up to work from home or anywhere outside of your office. But if you want to do that you can use queryinterface to get idispatch pointer but that is not converting you will be getting a new pointer. May i suggest that a check for idispatch is added to pywin32.
The following code samples demonstrate two approaches to consider make sure your arx projects supports the autocad activex client interfaces. Tech support scams are an industrywide issue where scammers trick you into paying for unnecessary technical support services. Manipulating the positions of desktop icons the old new. Use the automation interfaces inside your arx application. Ccomptr provides a specialization for idispatch that enables it to store pointers to com automation components and invoke the methods on the interface by using. How to get that idispatch interface you can read more here. Hi, if you want to find out all possible objects then you need a idispatch pointer to excel. I also tried inheriting directly from iunknown, but still i never reached the breakpoint in my version of queryinterface. Ccomptr is a basic smart pointer that wraps com interface pointers.
If we consider the other if statements important then we cant gloss over the failure on this one. You can help protect yourself from scammers by verifying that the contact is a microsoft agent or microsoft employee and that the phone number is an official microsoft global customer service number. I need to get this ipiehtmlinputhiddenelement interface from a ipiehtmlformelement element, but the input hidden interface seems to not be implemented. Once you have the pointer to iunknown you now have to ask for the actual interface that you would like to work with. Ccomptr provides a specialization for idispatch that enables it to store pointers to com automation components and invoke the methods on the interface by using late binding. The hresult returned from spselectionitem doesnt fail and mailptr2 is set now, however i run into issues when calling mailptr2s methods. How to cast dual interfaces of microsoft powerpoint. New inspector word editor crash outlook 2003 outlook. The windows mfc active template library atl information and. Hi all, i have a rather interesting issue with outlook 2003. If the call fails, an hresult is returned, which is the typical com pattern. Call queryinterface on the idispatch pointer, and ask for ihtmldocument2. And then im trying to to manipulate html which actually works in stand alone app with no problem. The ccomptr and ccomqiptr classes can help eliminate memory leaks by performing automatic reference counting.
By continuing to use pastebin, you agree to our use of cookies as described in the cookies policy. However, there are two things i didnt like about it. Application and id like to cast this idispatch to native documentwindow in order to call its methods and properties not via idispatch invoke, but directly. We use cookies for various purposes including analytics. If this is your first visit please consider registering so that you can post. With ccomqiptr, the return value is the pointer itself, and if the call fails, the internal hresult return value cannot be accessed. It means that you would get a pyidispatch instead of pyiunknown in those cases, but since pyidispatch is derived from pyiunknown this should. An introduction to active template library atl part 2. However, it seems that sometimes smart pointers are too smart in particular, im referring to the secret queryinterface ing assignment operator discussed by jared parsons on his blog. Ccomptr and releasing com objects manufacturing devblog. You then use queryinterface to in my interpretation tell the system that the idispatch object that swci points to is an icomponent2 object. I did change the declaration to ccomptr from ccomptr idispatch because i couldnt figure out how to convert between the two afterward. In this case we want to work with idispatch, which is a dynamic interface that lets us figure out which methods to call at runtime.
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