About DDE
Dynamic Data Exchange (DDE) makes it possible for two Windows applications
to communicate with each other by sending and receiving commands
and data. In this way, the applications can share data, execute commands
remotely, and check error conditions.
PowerBuilder supports DDE by providing PowerScript events and
functions that enable a PowerBuilder application to send messages
to other DDE-supporting applications and to respond to DDE requests
from other DDE applications.
Clients and servers
A DDE-supporting application can act as either a client or
a server.
About the terminology Used in connection with DDE, these terms are not related to client/server architecture,
in
which a PC or workstation client communicates with a database server.
A client application makes requests
of another DDE-supporting application (called the server). The requests
can be commands (such as open, close, or save) or requests for data.
A server application is the opposite
of a client application. It responds to requests from another DDE-supporting
application (called the client). As with client applications, the
requests can be commands or requests for specific data.
A PowerBuilder application can function as a DDE client or as
a DDE server.
In PowerBuilder, DDE clients and servers call built-in functions
and process events. DDE events occur when a command or data is sent
from a client to a server (or from a server to a client).