DDE Action Icon

DDE Action

Declaration

<AMDDE APPLICATION="text" ACTION="text [options]" TOPIC="text" ITEM="text" DATA="text" RESULTVARIABLE="text">

See Also

Registry

Description

The formal definition of DDE, or Dynamic Data Exchange is "an established protocol for exchanging data through active links between applications that run under Microsoft Windows."

Dynamic Data Exchange provides a channel for two Windows applications to communicate. Using Dynamic Data Exchange (DDE), one application -- referred to as the client application - can request information from, or send commands to, another application, referred to as the server application. The server application then processes the request from the client application. The server performs a task, such as updating data, or returning requested information to the client, such as an element of data maintained by the server application.

Practical Usage

Using the DDE action, AutoMate can become a DDE client, with the ability to send DDE requests and commands to DDE Server applications. Many popular Windows applications provide support for DDE, including Microsoft Word, Microsoft Excel,.ACT!, WinFax, Netscape and many more. It could be used for example to communicate with Netscape to tell the browser to reload the page or with Excel to populate a cell with data - all without having to send keystrokes to the application.

Parameters

General Tab

Application Name
Text, Required
MARKUP:APPLICATION="WINWORD"

Specifies the name of the application that the DDE Conversation should be initialized with. Usually (but not always) this is the name of the applications main EXE file (without the .EXE extension).

Topic
Text, Required
MARKUP:TOPIC="GENERAL"

Specifies the server-defined topic name of the DDE conversation. NOTE: The server application defines the topic names available for a DDE conversation. See the documentation for the DDE server application for specific information about the names of available topics.

Conversation Type
Text, Optional - default "execute"
MARKUP: ACTION="request"

Specifies the conversation method that will be used to communicate with the DDE Server application. The three types are Execute, Poke and Request. "Execute" and "Poke" are usually used to cause the DDE server application to do something whereas "Request" is usually used when trying to retrieve data from the DDE application Server so that it can be stored in a variable.

Command
Text, Optional - default "execute"
MARKUP: COMMAND="MyCommand"

Specifies the command string that the DDE Server should execute. NOTE: The server application defines the command strings supported for a DDE conversation. See the documentation for the DDE server application for specific information about the command strings you may send. "Command" is available only when Conversation Type [ACTION] is set to "Execute" otherwise it is ignored.

Item
Text, Optional - default "execute"
MARKUP: ITEM="myitem"

Specifies the server-defined item name of the DDE conversation. NOTE: The server application defines the item names available for a DDE conversation. See the documentation for the DDE server application for specific information about the names of available items. Item is available only when Conversation Type [ACTION] is set to "Poke" or "Request" otherwise it is ignored.

Data
Text, Optional - default "execute"
MARKUP: DATA="my data"

Specifies the data that should be passed to the DDE Server for use in the DDE conversation.

Variable
Text, Optional - default ""
MARKUP: RESULTVARIABLE="MYVARIABLENAME"

Specifies the name of an already created variable that should be populated with the return value from the DDE Server application after a Request has been made. This parameter is only available when Conversation Type [ACTION] is set to "Request" otherwise it is ignored.

Notes

For Advanced Users Only
AutoMate’s DDE capabilities should only be used by an experienced individual or one who is interested in becoming experienced with the use of DDE communications.

DDE Commands Supported are Determined by Application Manufacturer
For more information on the DDE commands supported by a particular software product, see the applications manual or contact the software’s manufacturer.

Standard Error Handling Options
This action also includes the standard "Error Causes" and "On Error" failure handling options/tabs

More on Error Handling Options

Variables and Expressions
All text fields allow the use of expressions by surrounding the expression in percentage signs (example: %MYVARIABLE%, %Left('Text',2)%). To help construct these expressions, a popup expression builder is available in all these fields by pressing F2.
More on variables...
More on expressions...
More on the expression builder...

Example