>We have a large application that we market to people that is written in VFP 9 SP1. We have a need to modularize some of the functionality. Specifically, to deal with PCI PA-DSS compliance, we want to isolate all of the credit/debit card processing functions into a separate module that can be versioned separately from the rest of our software and distributed as a separate file, be it a dll, exe, ocx, or whatever. This module needs to be able to support displaying data entry/progress screens as well as returning transaction results to the calling program.
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>What would be the best way to do this? I would like it to appear seamless to the end user, i.e. no separate entry on the taskbar for any windows it brings up, I would like any windows displayed to be clients of the main application window, etc.
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>Has anybody done anything like this for a VFP application? Is VFP the right tool to create this module in?
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>Thanks in advance for your help.

The quickest idea that comes to mind is to create an APP (not the exe) with all the logic included and call it from your main executable.