-> What is the simpliest and the most reliable way for the application
-> A to check that the application B is running and to send some
-> information (a set of strigs or such) to B after? (For example:
-> app.B is a scalable map showing different buildings, app.A contains
-> the list of these buildings, the task is to highlight a certain
-> building after it's name has been selected in the app.A.) Shall I
-> simply declare a message and send it to the app.B? Or  use DDE?
DDE will work pretty good for this type of thing. There are of course
other ways such as sending Windows Messages,OLE/COM, passing info
between files.
I haven't done much with DDE in Delphi, but I used it in
VB a few years back. It worked quite well. You can setup one program to
be a server and one to be the client. They can pass all types of info
between each as well as giving the ability to control and/or request
information from each other program.
Steve
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