Introducing Microsoft® Office InfoPath™ 2003

Validating Text Boxes with Custom Expressions

Order entry forms and invoice forms are good examples of InfoPath forms that require validation of several text box values. Most order entry and invoicing operations use online transaction processing (OLTP) with a direct network connection to the database. If the data entry program doesn’t include client-side data validation tests and relies on database constraints to ensure server-side data accuracy and consistency, users receive an error message from the server. Sending data that produces a server-side error and returns a message is called a round-trip. One of the goals of client-side data validation is to minimize round-trips to the database server.

When order entry or invoicing operations take ...