How to use Client resources in Appeon Web applications

Description

Appeon Web applications cannot directly interface with external resources from PowerBuilder code on the Client.

Workaround

Transfer Client resources to the Server, do all manipulations on the Server, and then return the result to the Client.

Example

The following example shows you how to use an n-tier NVO and a JSP page to work around a PowerBuilder application whose main functionality is updating a database using a text file at the Client.

The original PowerBuilder application

The main logic

Step 1: In a DataWindow control, save the specified column values as a text file on the Client.

Step 2: Modify the column values stored in the text file.

Step 3: Update the latest value stored in the text file to the database.

After modification

The main logic

Step 1: Encapsulate the following logic to an NVO.

  • Logic to save the specified column values as a text file.

  • Logic to update the latest value stored in the text file to the database.

Step 2: Deploy the NVO to EAServer as a Jaguar component.

Step 3: Call Jaguar component to save the column values as a text file on the Server.

Step 4: Read the contents of the text file and save it to the Client using IE browser.

Step 5: Modify the column values in the text file on the Client.

Step 6: Upload the text file to the Server using JSP.

Step 7: Use the functionality encapsulated in the Jaguar component to update the database.