OpenEdge provides several ABL statements to open and manage DDE conversations. The following table lists these DDE statements.

Table 1. DDE statements

Statement	Description
DDE ADVISE	Creates or removes a link to a DDE server data item. Creating a link allows ABL to trigger a DDE-NOTIFY event when the data item changes value.
DDE EXECUTE	Sends one or more application commands to the DDE server to execute.
DDE GET	Retrieves the new value of a linked data item in response to a DDE-NOTIFY event for the data item. You typically invoke this command in a DDE frame trigger block for the DDE-NOTIFY event.
DDE INITIATE	Opens a DDE conversation.
DDE REQUEST	Requests the current value of a server data item.
DDE SEND	Sends a new value to a server data item.
DDE TERMINATE	Closes a DDE conversation.

The following sections provide more information on how ABL structures DDE conversations and how to use these ABL statements to open, manage, and close DDE conversations. For a complete description of each statement, see ABL Reference.