Re: How to host a *ActiveX control hosted in IE*?
The textual persistence is a relatively new concept for controls,
introduced with IE. There's no other widely known container
that supports it. IPersistStreamInit and IPersistStorage have
been defined as persistence interfaces for OLE controls since
their inception in 1993 (OLE Controls is the former name of
ActiveX Controls).
The principle of persistence is that the container has no clue
about the persistent data of the objects it host (including
ActiveX Controls). This is certainly true for textual persistence
as well. In binary persistnce (and BTW, the same holds true
for textual persitnce too) the data is written by the control itself.
It's just that with textual persistence you also have a persistence
format that is easy to understand by humans and is publicly
documented for such controls. Still, you are not required to
write the PARAM tags yourself - tools like Visual InterDev
and FrontPage can happily do it for you by asking the controls
to save themselves via textual persistence - IPersistPropertyBag.
--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@mvps.org
MVP VC FAQ: http://www.mvps.org/vcfaq
=====================================
"Morgan Cheng" <morgan.chengmo@gmail.com> wrote in message
news:1155864509.362072.73270@h48g2000cwc.googlegroups.com...
Alexander Nickolov ??:
Most controls implement IPersistStreamInit (note no controls
I know of implement IPersistStream - it's kind of prohibited
for ActiveX Controls) in addition to IPeristPropertyBag.
I believe that IPropertyBag is good for plain text environment like web
page, since html <param> tag can be put into IPropertyBag directly.
IStream represents binary byte-stream which can only be understood by
control itself.
I am wandering how does Container know the content of IStream needed by
any possible control? Say, container got a list of property-value pair.
How can it translate it into an IStream?
If you need to implement support for IPersistPropertyBag,
implementing IPropertyBag is relatively straightforward...
--
=====================================
Alexander Nickolov
Microsoft MVP [VC], MCSD
email: agnickolov@mvps.org
MVP VC FAQ: http://www.mvps.org/vcfaq
=====================================
"Morgan Cheng" <morgan.chengmo@gmail.com> wrote in message
news:1155779524.581136.140270@i42g2000cwa.googlegroups.com...
ActiveX control can support several kind of IPersist* interface.
However, from IE's perspective, it prefer IPersistPropertyBag since the
persistent info for ActiveX control hosted in IE comes from <param>
tag. HTML is plain text. It is not surprsing that IE prefer ActiveX
control to support IPropertyBag which stores plain text of
property-value pair.
The problem is that CAxWindow/CAxHostWindow create ActiveX only with
IStream. That is, It expects hosted ActiveX control supports
IPersistStream. It is a gap between IE and ATL.
How can I host a ActiveX control expected to be run in IE(i.e. only
support IPersistPropertyBag) with ATL? Should I modify some ATL code?
or is there any better way?
Thanks