DDE Call back and it's parameters and values

From: Sonnich Jensen (sonnich.jensen_at_elektrobit.com)
Date: 02/27/04 

Date: 27 Feb 2004 06:22:21 -0800

Hi all!

I am playing around with DDE inspired by the article here:
http://bdn.borland.com/article/0,1410,16177,00.html
(correct TCallBack to TFNCallBack - other changes can be done too)

Also, I have problems when having more than 14 items on a
TDDEClientConv. (I run 42 at the moment)

I have a connection and can get data and poke them too. I use Excel as
a server for now. But I cannot get my programme to respond when data
changes.

My problem is that CallType is always 0 or 1 in:

function CallbackProc(CallType, Fmt: Word; Conv: HConv; hsz1, hsz2:
HSZ;
  Data: HDDEData; Data1, Data2: Longint): HDDEData; export;

Even when looking at Delphi own's function (in DdeMan) I am convinced
that it should work, but not. I tried to look for a detailed
describtion of this function and it parameters, is there such on the
net?
I also found that Conv seems to hold the parameter I need sometime.
When CallBack is 1, it is when data changes, when callback is 0 it is
when the connection is closed, or - sometimes just at random?

This has been mentioned before here, in 1997, but there is no answer.

BR
Sonnich Jensen

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