General tab for DDE Client
Use the General tab to specify details about communicating with the DDE client application.
Page 1 Settings
Server name list
From the Server name list drop-down list and push button, specify the server you want to use this DDE Client part with. You can type the name of the server directly in the field if you know its name.
When you select the Update List push button, the drop-down list is filled with the currently active DDE servers in the system. You can then select from the list of servers provided in the drop-down list.
For Windows:
In the Windows environment, to query the set of active DDE servers, you must select Client in same application as server on the DDE Server - Settings window. However, if you the DDE client application and DDE server application are in different application executables, then you must deselect Client in same application as server on the DDE Server - Settingswindow before packaging your application.
Topic list
From the Topic list drop-down list and push button, specify the topic you want to use this DDE Client part with. You can type the name of the topic directly in the field if you know its name.
When you select Update List, the drop-down list is filled with the topics supported by the server you selected in the Server name list drop-down list. The server must be running in order for the topics to be added to the drop-down list.
Items table
The Items table shows the items and formats of the items that you want to exchange with the DDE server application. A new row must be added for each item and format you want to provide to the DDE server application.
The items you add to this list appear as part of the public interface of the DDE Client part.
You can use the push buttons along the bottom to help manage the list of items.
Data format
From the Data format drop-down list and push button, specify the format of the data you want to pass between the DDE client application and DDE server application.
If you do not have an item selected in the table, the Apply push button is not available.
The format you select in this field is applied to the selected row in the table. Any new items added as rows to the table use the format specified in this field.
Data exchange push buttons
Use the push buttons at the bottom of the page to work with the items in the Items table:
New
Select New to add a new data item to the table. The format specified in the Data format field is used.
Delete
Select Delete to delete a data item from the table. The specified item and format are removed from the public interface for the part. You need to remove any connections made to the items that you delete.
Delete all
Select Delete all to delete all data items from the DDE Client table. The specified item and format are removed from the public interface for the part. You need to remove any connections made to the items that you delete.
Add supported items
Select Add supported items to add all of the items and formats supported by the selected server and topic to the DDE Clienttable. The server must be running to add these supported items.
Because the formats for each item can typically not be retreived, the format is set to string. You can then change the formats of the items to be what the server requires. Refer to the specific server application documentation for more information on the formats of the items.
Page 2 Settings
DDE Conversation timeout (ms)
In the DDE Conversation timeout (ms) field, type the number of milliseconds you want the DDE client application to wait before timing out when attempting to start a DDE conversation. The default value is 1000 milliseconds.
When setting the time-out value, consider the fact that DDE conversations are synchronous.
If a time out occurs, the lastTransactionError attribute contains the time-out error.
Connected server initial command
In the Connected server initial command field, type the name of the command you want to send to the server when you start a DDE conversation. If you specify a name in this field, the server is initialized prior to the conversation.
Server Program
Under Server Program, specify the details about the server program using the following fields:
Server program name
Specify the name of the program you want to run to start the server.
Server program input
Specify the command-line parameter you want sent to the server application that the DDE Client part is starting.
Server program timeout (ms)
Specify the maximum number of milliseconds the DDE client application waits before assuming the server cannot be started.
Number of server startup retries
Specify how many times you want to try to start the program within the allotted timeout period.
Last modified date: 05/13/2020