Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!world!goodearl
From: goodearl@world.std.com (Robert Goodearl)
Newsgroups: comp.windows.ms.programmer
Subject: Re: DDE Questions/Information, please...
Message-ID: <1991Jan13.062050.15754@world.std.com>
Date: 13 Jan 91 06:20:50 GMT
References: <17497@brahms.udel.edu>
Organization: The World @ Software Tool & Die
Lines: 58

In article <17497> garrett@brahms.udel.edu (Joel Garrett) writes:
>Hello all, I have a question regarding DDE, specifically pertaining to the DDE
>section of the Petzold book (Chapter 17)...
>
>Can I just type in the same info into an Wingz Spreadsheet cell (=DDEPOP|US_
>Population!US) and have the same result?
Can't help you with this one, what does the Wingz doc say about DDE macros?
>
>Also, is it possible to send messages in the opposite direction as in this
>example so that, for example, I could have a DDE client start up excel, have
>excel open up a file that had been specified in an earlier dialog in the client
>possibly perform some simple transformations and then send the transformed data
>to the client for further use?

Yes.  Any program can be either a client or a server, or both.  Excel supports
DDE as both a client and a server.  Though I've only seen Word-for-Windows
documented as being a server, apparently it also provides some client
services.

>  Is it possible to send commands and such to
>Excel from the client to do things like execute excel commands and macros and
>such?

Yes

>  I assume there would have be some documentatio somewhere of the standard
>Excel DDE Topics and Items? 

Excel (and many other DDE _server_ applications) advertise the standard
topic "system."  Many general services are available under this topic.
Otherwise, you can assume each open spreadsheet will answer to a topic
of the same name (as long as the "Ignore Remote Requests" box is not
checked from the Options/Workspace menu" -- available only when full menus
are set.)

There is documentation available, but my Excel docs are at work so I can't
direct you.  I know that there are some macros specifically for DDE.

****************

If you are going to write an app that supports DDE, I suggest you play with
the sample apps (both client and server) that come with the SDK.  I also
HIGHLY recommend the shareware program DDEWatch by John Hauck of Horizon
Technologies (75226.3136@compuserve.com -- tell him I sent you.)  This DDE
message monitor was invaluable to me when writing DDE support for the
Windows version of EASEL.  Horizon also has a DDE support DLL that they
sell.  If you're writing an app that needs to support DDE it's well worth
your time to check it out.  The feature list looked good to me, but I had
special constraints in writing support for a language that didn't allow me
to use it.

I'm in the process of writing an introductory paper on DDE.  Though it will
have specifics of EASEL support for DDE, I think there is enough general
information to be useful to someone trying to understand DDE.  If you'd like
a copy, let me know.  (If enough people ask, I'll see about posting it here.)
It'll be done by mid February.
-- 
Bob Goodearl -- goodearl@world.std.com