Using XML with Legacy Business Applications

Input and Import

If you have existing validation routines for import and data entry, reusing them for XML import will save you a lot of work. As I said earlier, there are limits to schema validation. If your application needs to validate order item numbers by looking them up in a database, you'll need to call this code when you import XML data. A well-designed system might use the same modules for validating an imported purchase order that it does for one entered by a human operator. If your system isn't coded this way, building in XML support might be a good opportunity for centralizing and cleaning up your validation logic.

The specific changes you need to make in your code depend on how you import data from the user's perspective. Do you provide ...