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. Using DDE, 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).