IN THIS CHAPTER
Validating data as it is being entered
Validating data immediately prior to submission
Organizing complex data-validation tasks
You have two opportunities to perform data-entry validation in a form: as the user enters data into the form and just before the form is submitted. We recommend you take advantage of both of these opportunities.
The most convenient time to catch an error is immediately after the user makes it—especially for a long form that requests a wide variety of information. You can make the user's experience less frustrating if you catch an entry mistake just after the user enters the information: his or her attention is already focused on the nature ...