Open DDE channel

Command group Flag affected Reversible Execute on client Platform(s)
Exchanging data YES YES NO Windows

Syntax

Open DDE channel {program-name | topic-name}

Description

This command opens the current channel for exchanging data. If there is a valid response, the flag is set and the channel is successfully opened. If the channel is already open, the existing conversation is closed.

When entering the command in a method, you use the parameters to specify the program and the topic to which the message is to be addressed. Note that the "pipe" (or vertical bar) between the program name and topic name is required.

This command is reversible, that is, a previous conversation will reopen if this command is contained within a reversible block.

When the command is used in a method containing a reversible block, and if a new conversation is initiated using the same channel number as an existing conversation, the original continues to process incoming messages only, and at the end of the method, the new conversation is stopped and the original becomes fully active.

Example

Set DDE channel number {2}
Open DDE channel {Omnis|Country}
If flag false
  OK message {The Country library is not running}
Else
  Do method TransferData
  Close DDE channel
  OK message {Update finished}
End If