Technique G84:Providing a text description when the user provides information that is not in the list of allowed values

Description

When users enter input that is validated, and errors are detected, the nature of the error needs to be described to the user in manner they can access. One approach is to present an alert dialog that describes fields with errors when the user attempts to submit the form. Another approach, if validation is done by the server, is to return the form (with the user's data still in the fields) and a text description at the top of the page that indicates the fact that there was a validation problem, describes the nature of the problem, and provides ways to locate the field(s) with a problem easily. The "in text" portion of the Success Criterion underscores that it is not sufficient simply to indicate that a field has an error by putting an asterisk on its label or turning the label red. A text description of the problem should be provided.

When input must be one of a set of allowed values, the text description should indicate this fact. It should include the list of values if possible, or suggest the allowed value that is most similar to the entered value.

Examples

• The user inputs invalid data on a form field. Before the user submits the form, an alert dialog appears that describes the nature of the error so the user can fix it.
• The user inputs invalid data on a form field and submits the form. The server returns the form, with the user's data still present, and indicates clearly in text at the top of the page that there were input errors. The text describes the nature of the error(s) and clearly indicates which field had the problem so the user can easily navigate to it to fix the problem.

Tests